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What is Intel's Hyper Threading?

Intel's Hyper-Threading technology has finally made it to market, courtesy of the latest Xeon processors. Hyper-Threading is a clever way of making a single chip operate like two separate devices without implementing two cores on one die. That, claims Intel, makes for higher performance without having to resort to significantly larger chips or even adding a second processor to the system.

So how does it work? HT is Intel's implementation of a technique known as Simultaneous Multi-Threading (SMT), a technology originally mooted for the cancelled EV8 Alpha processor. It's also going to be implented in IBM's Power5 processor, due 2004. Programmers have long known that some applications will run more efficiently if they're coded into a series parallel tasks, called threads. Modern multi-processing operating systems can then schedule those threads to operate on each of a system's two or more CPUs, just as it schedules the applications and other processes themselves.

Intel's technology essentially fools the operating system into thinking it's hooked up to two processors, allowing two threads to be run in parallel, both on separate 'logical' processors within the same physical processor. The OS sees double through a mix of shared, replicated and partitioned chip resources, such as registers, maths units and cache memory.

Go to Intels site for more info: link

What is a Subnet?

A subnet (short for "subnetwork") is an identifiably separate part of an organization's network. Typically, a subnet may represent all the machines at one geographic location, in one building, or on the same local area network (LAN). Having an organization's network divided into subnets allows it to be connected to the Internet with a single shared network address.

Once a packet has arrived at an organization's gateway or connection point with its unique network number, it can be routed within the organization's internal gateways using the subnet number as well. The router knows which bits to look at (and which not to look at) by looking at a subnet mask. A mask is simply a screen of numbers that tells you which numbers to look at underneath. In a binary mask, a "1" over a number says "Look at the number underneath"; a "0" says "Don't look." Using a mask saves the router having to handle the entire 32 bit address; it can simply look at the bits selected by the mask.

Using the previous example (which is a very typical case), the combined network number and subnet number occupy 24 bits or three of the quads. The appropriate subnet mask carried along with the packet would be:

255.255.255.0

Or a string of all 1's for the first three quads (telling the router to look at these) and 0's for the host number (which the router doesn't need to look at). Subnet masking allows routers to move the packets on more quickly.

If you have the job of creating subnets for an organization (an activity called subnetting) and specifying subnet masks, your job may be simple or complicated depending on the size and complexity of your organization and other factors.

Read more here

What is DirectX?

Your video card has a limited set of features. Those features are DX8.1 compliant, meaning the card has hardware support for all of the features contained in DX8.1.

Now, you can install DX9 on your system, but it doesn't make your video card develop new hardware features that it didn't have before. So, any new features introduced in DX9 that were not included in DX8.1 will simply not be used by your card. These features will be ignored, and only DX8.1 features will be used.

DirectX is backwards compatible, so even if your card doesn't have all of the features of the latest version of DX, it will still work with it. Unsupported or missing hardware features will simply be ignored, or in a few cases, may revert to an earlier method which is supported by your card.

What's an IP address?

So what is an IP? Every machine on the Internet has a unique identifying number, called an IP Address. A typical IP address looks like this:

• 216.27.61.137

To make it easier for us humans to remember, IP addresses are normally expressed in decimal format as a "dotted decimal number" like the one above. But computers communicate in binary form. Look at the same IP address in binary:

• 11011000.00011011.00111101.10001001

The four numbers in an IP address are called octets, because they each have eight positions when viewed in binary form. If you add all the positions together, you get 32, which is why IP addresses are considered 32-bit numbers. Since each of the eight positions can have two different states (1 or 0) the total number of possible combinations per octet is 28 or 256. So each octet can contain any value between 0 and 255. Combine the four octets and you get 232 or a possible 4,294,967,296 unique values! Out of the almost 4.3 billion possible combinations, certain values are restricted from use as typical IP addresses. For example, the IP address 0.0.0.0 is reserved for the default network and the address 255.255.255.255 is used for broadcasts. The octets serve a purpose other than simply separating the numbers. They are used to create classes of IP addresses that can be assigned to a particular business, government or other entity based on size and need. The octets are split into two sections: Net and Host. The Net section always contains the first octet. It is used to identify the network that a computer belongs to. Host (sometimes referred to as Node) identifies the actual computer on the network. The Host section always contains the last octet. There are five IP classes plus certain special addresses: What types of IP's are there? There are two types, public and internal. Public IP's are assigned to you by your ISP or Network Administrator that gets them from your provider. There are 5 classes of Public IP's:

• Class A - This class is for very large networks, such as a major international company might have. IP addresses with a first octet from 1 to 126 are part of this class. The other three octets are used to identify each host. This means that there are 126 Class A networks each with 16,777,214 possible hosts for a total of 2,147,483,648 unique IP addresses. Class A networks account for half of the total available IP addresses. In Class A networks, the high order bit value (the very first binary number) in the first octet is always 0.
• Class B - Class B is used for medium-sized networks. A good example is a large college campus. IP addresses with a first octet from 128 to 191 are part of this class. Class B addresses also include the second octet as part of the Net identifier. The other two octets are used to identify each host. This means that there are 16,384. Class B networks each with 65,534 possible hosts for a total of 1,073,741,824 unique IP addresses. Class B networks make up a quarter of the total available IP addresses. Class B networks have a first bit value of 1 and a second bit value of 0 in the first octet.
• Class C - Class C addresses are commonly used for small to mid-size businesses. IP addresses with a first octet from 192 to 223 are part of this class. Class C addresses also include the second and third octets as part of the Net identifier. The last octet is used to identify each host. This means that there are 2,097,152 Class C networks each with 254 possible hosts for a total of 536,870,912 unique IP addresses. Class C networks make up an eighth of the total available IP addresses. Class C networks have a first bit value of 1, second bit value of 1 and a third bit value of 0 in the first octet.
• Class D - Used for multicasts, Class D is slightly different from the first three classes. It has a first bit value of 1, second bit value of 1, third bit value of 1 and fourth bit value of 0. The other 28 bits are used to identify the group of computers the multicast message is intended for. Class D accounts for 1/16th (268,435,456) of the available IP addresses.
• Class E - Class E is used for experimental purposes only. Like Class D, it is different from the first three classes. It has a first bit value of 1, second bit value of 1, third bit value of 1 and fourth bit value of 1. The other 28 bits are used to identify the group of computers the multicast message is intended for. Class E accounts for 1/16th (268,435,456) of the available IP addresses.

Private IP ranges:

• 10.0.0.0 to 10.255.255.255
• 172.16.0.0 to 172.31.255.255
• 192.168.0.0 to 192.168.255.255

What is NTFS / FAT32?

FAT32:

The existing File Allocation Table (FAT) file system was invented in 1977 as a way to store data on floppy disks for Microsoft stand-alone Disk Basic. Although originally intended for floppy disks, FAT has since been modified to be a fast, and flexible system for managing data on both removable and fixed media. In 1996 Windows 95 OSR2 came out with FAT32 a new and improved FAT.

FAT32 provides the following enhancements over previous implementations of the FAT tile system: Supports up to 2 terabytes in size

Uses space more efficiently. FAT32 uses smaller clusters (e.g. 4kb clusters for drives up to 8GB in size), resulting in up to 5% more efficient use of disk space relative to large FAT drives. The following chart is an example of what the cluster size would be for the various sizes of hard drives as you can see a 32GB drive or larger will support the same cluster size as FAT16.

NTFS:

Short for NT File System, one of the file system for the Windows NT operating system (Windows NT also supports the FAT file system). NTFS has features to improve reliability, such as transaction logs to help recover from disk failures. To control access to files, you can set permissions for directories and/or individual files. NTFS files are not accessible from other operating systems such as DOS.

So, which has better security, features, control and stability?

NTFS has all those features and more. The main benefit of NTFS is the security. You can set file and folder level permissions to different user groups.

Some of the features you can use when you choose NTFS are:

• Domains, which are part of Active Directory, and which you can use to fine-tune security options while keeping administration simple. Domain controllers require NTFS.
• File encryption, which greatly enhances security.
• Permissions that can be set on individual files and on folders.
• Sparse files. These are very large files created by applications in such a way that only limited disk space is needed. That is, NTFS allocates disk space only to the portions of a file that are written to.
• Remote Storage, which provides an extension to your disk space by making removable media (such as tapes) more accessible.
• Recovery logging of NTFS meta data, which helps you restore information quickly in the event of power failure or other system problem. This allows access to the volume immediately after restarting the computer without waiting for chkdsk.exe to run.
• Disk quotas, which you can use to monitor and control the amount of disk space used by individual users.
• Better scalability to large drives. The maximum drive size for NTFS is much greater than that for FAT, and as drive size increases, performance with NTFS doesn't degrade as it does with FAT.

You can still do all the same things that you could with the FAT32 system.

NTFS is much faster then FAT32.

Anymore questions, ask away in the proper forum.

What's the difference between a router / switch / hub?

• Hub:
  Also known as a dumb hub. Hubs are general repeaters that share bandwidth between other devices connected to it. If you have a 100Mb hub and 4 ports, and 4 devices connected to the hub, each device is using the same 100Mb bandwidth. So, if PC1 is pushing a large amount of files, that will slow down the other devices connected to that hub. PC1 is using 1/2 of the resources the hub is designed for, so, the rest of the machines share the remaining resources. This results in poor performance which can result in data colisions. Another down side to a hub is that it broadcasts to each PC since it's not smart enough to remember where each device is.
• Switch:
  There are two types of switches, managed and unmanaged switches. Unmanaged switches are more common in homes and SOHO settings. Switchs are Collision detection and prevention and each port is allocated 100Mb. Meaning each device does not share the bandwidth resulting in faster network performance.
• Router:
  There are different types of routers, what will be explained are home routers. A router is a switch that acts as a DHCP (Dynamic Host Configuration Protocol), and sometimes a NAT server. All that means is that it can assign any device connected to it an IP, Subnet, Gateway and DNS servers automatically. Usually NAT will function as a firewall between your PC's and your internet connection.
  This will make sharing an internet connection and file sharing easier for home users who do not have a dedicated server to function as the "router".

What's the difference between Full-duplex and half-duplex? Full duplex allows two devices to send / receive data at the same time, just like you can with someone on a telephone. A good example of half-duplex is a walkie-talkie, only allowing once device to send / receive at a time.

What's IPv6?

IPv6 is short for "Internet Protocol Version 6". IPv6 is the "next generation" protocol designed by the IETF to replace the current version Internet Protocol, IP Version 4 ("IPv4").

Most of today's internet uses IPv4, which is now nearly twenty years old. IPv4 has been remarkably resilient in spite of its age, but it is beginning to have problems. Most importantly, there is a growing shortage of IPv4 addresses, which are needed by all new machines added to the Internet.

IPv6 fixes a number of problems in IPv4, such as the limited number of available IPv4 addresses. It also adds many improvements to IPv4 in areas such as routing and network autoconfiguration. IPv6 is expected to gradually replace IPv4, with the two coexisting for a number of years during a transition period.

Go to IPv6's site for more info or here for more info from Microsoft.

How do I determine what my PC specs are?

So you have you've always wanted to know what you have for hardware inside your PC, but you could never figure out how to find out with out opening up your computer. With this mini guide, we can help you find out what hardware you have.

There are times when you may have to just go inside your case and look around. But, for now we will describe how to determine what you have through a few different pieces of software.

Here's a list of freeware programs you need to download:

• CPUID
• Belarc Advisor
• PC Wizard 2004
• Sandra

These programs will give you detailed information about your PC. A lot of it you don't really NEED to know unless your a PC buff. These will usually give you a general idea of what you have also.

If you need help reading these programs, ask one of the Staff members or forum members in a new Thread and we will help you.

What is Spyware?

Spyware is Internet jargon for Advertising Supported software (Adware). It is a way for shareware authors to make money from a product, other than by selling it to the users. There are several large media companies that offer them to place banner ads in their products in exchange for a portion of the revenue from banner sales. This way, you don't have to pay for the software and the developers are still getting paid. If you find the banners annoying, there is usually an option to remove them, by paying the regular licensing fee.

Why is it called "Spyware"?
While this may be a great concept, the downside is that the advertising companies also install additional tracking software on your system, which is continuously "calling home", using your Internet connection and reports statistical data to the "mothership". While according to the privacy policies of the companies, there will be no sensitive or identifying data collected from your system and you shall remain anonymous, it still remains the fact, that you have a "live" server sitting on your PC that is sending information about you and your surfing habits to a remote location...

And best of all, spyware is not illegal.

Real spyware...
There are also many PC surveillance tools that allow a user to monitor all kinds of activity on a computer, ranging from keystroke capture, snapshots, email logging, chat logging and just about everything else. These tools are often designed for parents, businesses and similar environments, but can be easily abused if they are installed on your computer without your knowledge.

These tools are perfectly legal in most places, but, just like an ordinary tape recorder, if they are abused, they can seriously violate your privacy.

How do you remove spyware?
You need to have Anti-Spyware tool(s). Check out these two:   LavaSoft or Microsoft AntiSpyware

Check out our Handy Tools section as well for helpful tools.

So how do I get infected?

You usually get infected because your security settings are too low. This FAQ is mainly for Internet Explorer. Note that Windows XP's IE6 w/ SP2 will strengthen IE's security

Here are a number of recommendations that will help tighten them, and which will contribute to making you a less likely victim:

1. Watch what you download!
   Many freeware programs, and P2P programs like Grokster, Imesh, Kazaa and others are amongst the most notorious, come with an enormous amount of bundled spyware that will eat system resources, slow down your system, clash with other installed software, or just plain crash your browser or even Windows itself.
2. Go to IE | Tools | Windows Update | Product Updates, and install ALL Security Updates listed.
   It's important to always keep current with the latest security fixes from Microsoft.
   Install those patches for Internet Explorer, and make sure your installation of Java VM is up-to-date. There are some well known security bugs with Microsoft Java VM which are exploited regularly by browser hijackers.
3. Go to Internet Options| Security | Internet, click "default level", then OK.
   Now press "Custom Level."
   In the ActiveX section, set the first two options ("Download signed and unsigned ActiveX controls) to 'prompt', and 'Initialize and Script ActiveX controls not marked as safe" to 'disable'.
   Now you will be asked whether you want ActiveX objects to be executed and whether you want software to be installed.
   Sites that you know for sure are above suspicion can be moved to the Trusted Zone in Internet Option/security.
   So why is activex so dangerous that you have to increase the security for it?
   When your browser runs an activex control, it is running an executable program. It's no different from doubleclicking an exe file on your hard drive.
   Would you run just any random file downloaded off a web site without knowing what it is and what it does?

What is the difference between DDR and SDRAM?

SDRAM
(synchronous DRAM) has become the standard type of memory for PCs. The main reason for this is that SDRAM is tied to the front-side bus clock in your system. SDRAM and the bus execute instructions at the same time rather than one of them having to wait for the other. As bus speeds have increased beyond 100MHz, this has improved system performance.

DDR SDRAM
DDR (double data rate) memory is the next generation SDRAM. Like
SDRAM, DDR is synchronous with the system clock. The big difference between DDR and SDRAM memory is that DDR reads data on both the rising and falling edges of the clock signal. SDRAM only carries information on the rising edge of a signal. Basically this allows the DDR module to transfer data twice as fast as SDRAM. For example, instead of a data rate of 133MHz, DDR memory transfers data at 266MHz.

DDR modules, like their SDRAM predecessors, are called DIMMs. They use motherboard system designs similar to those used by SDRAM; however, DDR is not backward compatible with SDRAM-designed motherboards. DDR memory supports both ECC (error correction code, typically used in servers) and non-parity (used on desktops/laptops.)

Rambus DRAM
Rambus memory (RDRAM®) is a revolutionary step from SDRAM. It's a new memory design with changes to the bus structure and how signals are carried. Rambus memory sends less information on the data bus (which is 18 bits wide as opposed to the standard 32 or 64 bits) but it sends data more frequently. It also reads data on both the rising and falling edges of the clock signal, as DDR does. As a result, Rambus memory is able to achieve effective data transfer speeds of 800MHz and higher.

Another difference with Rambus memory is that all memory slots in the motherboard must be populated. Even if all the memory is contained in a single module, the "unused" sockets must be populated with a PCB, known as a continuity module, to complete the circuit.

Rambus DRAM modules are known as RIMM modules (Rambus inline memory modules). Rambus memory supports both ECC and non-ECC applications.

How do DDR and Rambus memory compare performance wise? Sorry, I know you don't want to hear this, that depends. Both technologies have their own ardent supporters and we have seen several different benchmarks to date that provide conflicting results.

On the surface, it seems simple: Data flow at 800MHz is faster than data flow at 266MHz, right? Unfortunately, it isn't that simple. While Rambus modules may have the ability to transfer data faster, it appears to have higher latency (the amount of time you have to wait until data flows) than that of a DDR system. In other words, the first data item transferred in a Rambus transaction takes longer to initiate than the first data item moved in a DDR system. This is due in part to how the systems are constructed.

In a DDR or SDRAM system, each DIMM is connected, individually and in parallel, to the data bus. So whether you have a single DIMM or multiple DIMMs, the amount of time it takes to initiate a data transfer is effectively unchanged.

In a Rambus system, RIMM modules are connected to the bus in a series. The first data item transferred must pass through each RIMM module before it reaches the bus. This makes for a much longer distance for the signal to travel. The result is higher latency. That's not necessarily a problem in an environment where data transactions involve lengthy streams of data, such as gaming. But it can become an issue in environments where many small transactions are initiated regularly, such as a server.

To further explain, here's an example that we can all relate to, driving your car to the store. You can take the roundabout freeway and drive 20 miles at 70 MPH. Or, you can take a more direct route and drive just 5 miles at 50 MPH. You might go faster on the freeway but you'll get to the store (Memory Controller) faster on the straight-line route.

How do I format my drive?

If you want to do a straight format, then the easist way is to get a Windows 98 boot disk, by either creating one in Windos 98 or going to Bootdisk.com.

Once you have this disk, boot w/ out CD-ROM support. Once your to the command prompt you will want to find out which drive letter is assigned to your actual drive (boot disks sometimes makes virtial drives). Run fdisk by typing FDISK. Delete all of your partitions. Exit FDISK and run this command just to be safe: fdisk /mbr

Now, go back into FDISK, create however may partitions that you want. Exit FDISK and reboot your PC with the bootdisk in the floppy drive and boot with it w/ out CD-ROM support again. Now, run this command format C:. Do this for all of the partitions you created.

Later on if you created 1 partition and left extra un allocated space and have Windows 2000 or XP, you can go into Disk Management and create more partitions.

Remember that formatting with a 98 boot disk will format with FAT32, not NTFS. If you want NTFS, you will have to use Windows 2000's or XP's setup wizard to format the drive for you after you create your partitions in the setup wizard.

Why doesn't my hard drive have the advertised amount of space?

When you buy 120 Gigabyte hard disk, you will never see the size reported as 120GB. This FAQ looks at the reason why and at the issues involved. It does not consider the issue of file system overheads which will further decrease the free space after formatting.

I'm sure that at some point someone has told you that a Kilobyte is 1024 Bytes. If we are pedantic about the terminology used in describing storage however, they are wrong. A Kilobyte is by definition 1000 bytes, Kilo literally denoting 10^3 of something. What they are talking about is, in fact, a Kibibyte (2^10 Bytes.) This inconsistency causes problems because when people start talking about computer storage - Kilo is suddenly used incorrectly to mean "2^10" rather than the proper "10^3."

Here Follows a quick terminology break:

• Giga- A Prefix meaning 1 Billion, or 10^9 of something.
• Kilo- A Prefix meaning 1 Thousand, or 10^3 of something.
• Gibi- A Prefix meaning 2^30 of something, derived from Gigabinary.
• Kibi- A Prefix meaning 2^10 of something, derived from Kilobinary.
• Equivalents for Mega-, Tera-, Peta-, etc. all exist in similar fashion.

While this seems a little fussy, it becomes important when talking about large quantities. The difference between a Kilobyte and a Kibibyte is 24 bytes (2^10 - 10^3,) an amount very few people are going to notice or care about. When we start looking at Gigabytes and Gibibytes however, the difference is 73,741,834 Bytes (2^30 - 10^9,) a significant quantity.

It naturally follows that as quantities get larger, this discrepancy increases. 120 Gigabytes translates to approximately 112 Gibibytes so naturally people feel cheated after formatting their new storage monster and finding less space than they expect. The amount in Gibibytes (and thus the amount of space that will be reported) can be calculated as follows:
Storage in Gibibytes = (Storage in Gigabytes)*(10^9)/(2^30)

So why don't hard drive manufacturers rate their drives in Gibibytes? Bizarrely enough, one pressing reason is to avoid confusing consumers. There have been movements to see KiB, MiB and GiB units introduced in storage to represent Kibibytes, Mibibytes and Gibibytes respectively. This would require re-branding of any products rated in the base 10 system as well as re-education of the end user. Marketing also comes into the equation as drive sizes increase. The first company to make the switch to Gibibytes would suddenly have a range of products that look smaller than their base 10 equivalents.

In the end, consistency is the most important point. Two different 120 Gigabyte drives are going to be almost exactly the same size regardless of manufacturer or model. The reasons for changing to a base 2 system simply aren't pressing enough to warrant the problems of doing so. It's a little annoying, but two minutes with a calculator will verify that 111.7 Gigs is, in fact, the correct amount of space for a 120 Gigabyte drive to be reporting.

What is RAID?

So what is RAID (Redundant Array of Independent Disk) ? Basically RAID can improve performance and provide redundancy (hence the name) if you select the right level. Here's a basic overview of the levels:

• RAID 0
  Provides data striping (spreading out blocks of each file across multiple disks) but does not have redundancy. RAID 0 provides improved performance.
• RAID 1
  Provides disk mirroring. This provides basic fault tolerance.
• RAID 3
  Does the same thing as RAID 0, but also requires a dedicated disk for error correction. Good read / write performance and little redundancy. Requires 3 disks
• RAID 5
  Provides data striping at the byte level and also error correction. Very good performance and true redundancy. Three disks are needed.

That's basically what RAID will do for you. Now, I'll go into more detail on each level.

How do I disable Windows Messenger Service?

Disabling the Messenger Service

To disable the sometimes annoying WMS popups follow these instructions:

Windows XP Professional

1. Click Start | Settings | Control Panel
2. Click Administrative Tools
3. Click Services
4. Double click Services
5. Scrolldown and highlight "Messenger"
6. Right click the highlighted line and choose Properties
7. Click the STOP button
8. Select Disable or Manual in the Startup Type scroll bar
9. Click OK

Windows 2000

1. Click Start | Settings | Control Panel | Administrative Tools | Services
2. Scroll down and highlight "Messenger"
3. Right click the highlighted line and choose Properties
4. Click the STOP button
5. Select Disable or Manual in the Startup Type scroll bar
6. Click OK

Windows NT

1. Click Start | Control Panel
2. Double Click Administrative Tools
3. In the Messenger Properties window, select Stop
4. Then choose Disable as the Startup Type
5. Click OK

Windows 98 & ME

• Windows Messenger Service cannot be disabled unfortunatley

What is Dual-Channel DDR?

A processor in a computer is like the engine of a car. A car needs gas to fuel its engine. Similarly, a computer CPU needs memory storage to process its data. Data must be stored in memory first, before being delivered to the processor. When more data can delivered to the CPU via memory at faster speeds, the CPU can manipulate instructions and data more efficiently and ultimately, the requested task can be accomplished in less time.

Data is filled into a funnel (memory); the funnel then channels the data through its pipe to the CPU's input. Dual-Channel memory utilizes two funnels and two pipes to feed data to the CPU, thereby being able to deliver up to twice the data of a single fennel. With two channels and funnels, data is transferred 128 bits at a time. The process works the same way when data is emptied from the CPU by reversing the flow of data. To prevent the funnel from being over filled with data or to reverse the flow of data through the funnel, here is a traffic controller shown as a valve on the funnels pipe. On your motherboard, there's a chip called a memory controller that handles all data transfers involving the memory modules and the CPU.

With dual channel memory, the memory controller is able to move double the peak amount of data that it could normally move with single channel memory. That's because it is sending or receiving data from the two memory module pairs at the same time.

Color depths and what they mean

Here's a general break down of the different color depths:

DVD-RW/R | DVD+RW/R ?

So what's the difference between DVD-R / -RW & DVD+R / +RW?

DVD-R / -RW
The originating DVD format that was compatible with most DVD players is DVD-R/RW. DVD-R/RW supports both single-sided (4.7 GB) and double-sided (9.4 GB) media. Due to the amount of time that DVD-R/RW has been out, many more stand alone DVD player are likely to support them. This format is pretty much your everyday use format. It is advised to use this format if you intend to create home movies, and other applications that would run from a stand-alone DVD player.

DVD+R / +RW
The new format is DVD+R/RW, which happens to be based on CD-RW technology. This format is becoming increasingly popular. The compatibility rate of this format however is not as high as the older format on stand-alone players. The introduction of the DVD+R/RW was created in the intent that the format would be completely compatible across both DVD optical drives in computers, and drives in stand-alone players. The format also allows for a mix of information on the media, such as not only video, but also data files. This is not to say that the previous format cannot be used for data, it is just to say that the creators of this format felt DVD+R/RW was a much better format to be used for both purposes. The DVD+R/RW format supports both CAV and CLV writing as well as lossless linking. CAV is an acronym for Constant Angular Velocity. This feature pretty much means that the data transfers at the same speed regardless of where it is being read off the disc; as opposed to Constant Linear Velocity which is dependant on the location of the disc being read. CLV is the method of transfer used by most of the older optical drives. The introduction of CAV allows the drive unit to operate without much trouble as it does not have to regulate the motor speed. This is an improvement over CLV which can run into problems on higher speed optical devices because of the brief latency when changing motor speed. Currently most DVD+R media are capable of writing at a maximum of 8x where as DVD-R is still at a 4x specification.

Over all, DVD+ RW / R is best to be used for computers as it's read times / write times are faster. If you want to distrobute your videos to DVD players in your living room, it's best as of now (early 2004) to use DVD-RW / R for this. Personally myself, I will use the + format since I only use my DVD discs for data.

For more technical information:

• DVDRW.com
• DVDforum.com

What is is the OSI model?

What is OSI and how important is it? OSI stands for Open Systems Interconnect. It is how every network "aware" application, NIC, switch, whether it's a managed or unmanaged switch, hub, router, firewall, etc communicates which the OS and each other.

The OSI model has 7 layers to it and each play an important role. Here are the layers in order:

1. Application
2. Presentation
3. Session
4. Transport
5. Network
6. Data-link
7. Physical

A very easy way to remember this is All People Seem To Need Data Processing. Here's an image of the OSI layer that may help as well:

Networking consists of basically sending data from one device to another. The sending PC must recognize the data, divide the data into manageable chunks, add info to each chunk to determine the destination and who can receive the data, add timing and error checking information to ensure the data is received the way it was sent, and finally pushes the data out. The receiving PC will do the opposite of the sender, it will take the data off the link, and processes it from 7-1 so to speak.

Each layer when sending or receiving does something different to each packet and passes it to the next layer.

Now, I'll give an overview of each layer's function.

Application layer:
Topmost layer of the OS Model. This layer relates to applications / services that support user apps, FTP, databases, email, chatting, etc.

Presentation layer:
Format that is used to exchange data among networked devices. Such as IBM - Apple - Sun. So, data that is received from the Application layer is transformed into a common language.

Session Layer:
Allows two apps to open, use and close sessions to communicate with each other. This layer handles the security, it puts checkpoints in the data stream. They break data into smaller groups, so if data is lost at one check point, only the data from that checkpoint is resent.

Transport Layer:
This layer works with the session layer ensuring that there is no data loss and that everything is sent in tact.

The sending device at this layer repackages messages, dividing long messages into smaller packets and collecting small packets together in one package. This ensures packets are transmitted efficiently. The device receiving the packets reassembles the original messages and sends an acknowledgment that it was received. This is the layer that TCP and SPX reside.

Network Layer:
This layer is responsible for addressing messages and translating logical addresses and names into phsyical address. Determines the route from the source to the destination computer. Determines which path is best for the data to follow on a network. It handles traffic problems and data priority as well. If the port on the router cannot transmit a data chunk as large as the source sends, this layer will compensates for breaking the data into smaller units. The receiving end reassembles the data. This layer is where IP and IPX reside.

Data-link Layer:
This layer sends data frames from the network layer to the phsyical layer. It controls the electrical pulses that enter and leave the physical layer. On the receiving end, this layer repackages the signals from the physical layer back into data frames.
Here's an example of a datapacket:


Bit patters tokens and encoding methods are known to this layer.

This layer is responsible for error free transfer of these frames from one device to another through the physical layer.

Physical Layer:
This layer is responsible for transmitting the rata data packets over a physical medium or wireless medium.

This layer also synchronizes bits and encoding. This layer is the physical layer on which it decides how data is sent through a NIC port, switch and media (CAT5, BNC, wireless, etc).

I have two installs of Windows... how do I remove one?

There's been a lot of threads @ BD asking how to edit the boot.ini file and how they accidently installed two operating systems.

This is a pretty easy fix, usually. There's a few ways to edit your boot.ini file, follows these steps and you will be on your way to reconfiguring your boot.ini file in no time:

Windows 2000 / Windows XP

1. Right click on My Computer | Properties
2. Click the Advanced Sheet
3. Under Startup & Recovery click Settings
4. Look for "To edit the Startup files manually, click Edit" | Click Edit
5. Here you will see your boot.ini file
6. Simply edit out the second OS or whichever one that you do not want. Make sure that you print out your original boot.ini file just incase .
   

Recovery Console route

1. Insert your 2000 / XP CD and boot from it
2. Select "R" for recovery / repair
3. Select "C" for Recovery Console
4. Select the OS, preferably the first one and type in your local Admin password
5. Now, from the prompt type: bootcfg /copy then bootcfg /scan and you can edit from there

So, what does all this information mean in the boot.ini file?

[boot loader]

timeout=30

default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS

[operating systems]

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /NoExecute=OptIn

Basically, under the [operating systems] section, you will see one instance (see above) or two (see below)instances of an OS, or even more.

[boot loader]

timeout=30

default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS

[operating systems]

multi(0)disk(1)rdisk(0)partition(1)\WINDOWS="Windows XP Professional" /fastdetect

multi(0)disk(0)rdisk(0)partition(2)\WINNT="Windows 2000 Professional" /fastdetect

Simply Remove the OS / line you do not want. Then, boot into Windows and find the partition that the other OS was installed on and format it.

Here's a KB article from Microsoft that has more information.

Environment Variables

Environment variables can come in handy when you need to create a shortcut, or get to a folder quickly. EV are used for a lot of things. This applies to Windows 2000 and Windows XP.

It's easy it link to an EV:
%windir%\explorer.exe

So, what does this mean and what's so special about it? Basically, it allows you to create a dynamic link to a file. Dynmaic meaning that if the Windows Directory or any other EV path changes, it won't matter, the EV will know where the path is.

Here's a list of Environment Variables: (I'm not sure if this is all- PM James if you have more)

• %appdata%
  This will bring you to your Application Data folder, which is hidden by default. This holds customizations of your apps.
• %systemroot% | %windir%
  This will bring you to your Windows installtion directory.
• %systemdrive%
  This will bring you to your "My Computer".
• %comspec%
  Brings you to a CMD prompt.
• temp
  Brings you to the temporary folder.
• %tmp%
  Brings you to your profile's temp folder.
• %homedrive%
  Brings you to your home directory if you have one mapped to your profile. Active Directory Profile setting.

What are the differences between the P4 families?

Last updated: September 2004
Confused by all of the Pentium 4 families? It can be tricky, but there are some differences between all of them.

Here's the general breakdown of each family:

• Northwood
• Prescott

Then, in those two families, there are classes.

• P4
• P4 A
• P4 B
• P4 C
• P4 E

Each class has it's own features. The higer the alphabet, the more advanced the CPU is. A letter is only applied if there are tow different models with the same core clock speed. For example, the P4 2.4 / FSB of 400 MHz, and the P4 B 2.4 / FSB of 533 MHz.

AMD naming scheme

Q. What does the # in the AMD processor's name mean?

A. Now lets use Athlon XP 2800+ as an example. "2800+" a performance model number, therefore, this processor competitively compares to a processor running a 2.8GHz or 2800MHz. Even though the processor is 2.083GHZ it has the same performance of a 2800mhz chip.

Frequency Alone does not determine performance.

Megahertz is only one contributing factor to overall performance. The other major factor is the amount of work the processor can complete in a given clock cycle, or "Instructions per Clock" (IPC).

True Performance = MHz x IPC

Q. What does the "xp" mean?

A. XP = "XTREME PERFORMANCE" means that the chip was designed for Microsoft's Windows XP. It's basically a marketing scheme to make consumers think this is "needed" for Windows XP.

Here is a link with information performance vs. frequency.

This information was gathered from a technician from AMD's site:

AMD Athlon XP processor has QuantiSpeed architecture, which is designed to deliver the optimum balance of work per clock cycle and frequency scalability, giving end users the best performance across a wide array of application-based benchmarks.

Q. What is QuantiSpeed Architecture?

A. QuantiSpeed architecture is a term which encompasses the AMD Athlon™ XP processor's core architectural features. It allows the AMD Athlon XP processor to accomplish more instructions per clock cycle (IPC), providing superior application performance. Improved IPC is a result of the following technological advances:

• Nine-issue, superscalar, fully pipelined microarchitecture: Provides more pathways to feed application instructions into the execution engines of the core, allowing the processor to complete more work in a given clock cycle (high IPC). The delicate balance between the depth of the pathways and clock speed of the processor produces high levels of performance.
• Superscalar, fully pipelined Floating Point Unit (FPU): Completes more floating point operations per clock cycle than competitive x86 processors and permits high operating frequencies. The end result is a processor with the computing power to tackle the most computation-intensive software applications.
• Hardware data prefetch: Prefetches data from system memory to the processor's Level 1 cache, which reduces the time it takes to feed the processor critical data, increasing work throughput and therefore overall performance.
• Exclusive and speculative Translation Look-aside Buffers (TLBs): Keep the maps to critical data close to the processor, which helps prevent the processor from stalling or waiting when future data is requested. These TLB structures are now larger, exclusive between caches, and speculative. Larger TLB's give the AMD Athlon XP processor access to additional data maps. Exclusivity removes the duplication of information, freeing up more space in the Level 2 cache for other useful data to be used by the processor. And the speculative nature of these structures allows the processor to generate future maps of critical data quickly.

These four key advances allow QuantiSpeed architecture to perform more calculations per second, boosting overall productivity and enabling an ultimate computing experience. For additional information, download the QuantiSpeed Architecture white paper from the AMD Athlon XP Processor White Papers page.