HOW TO BUILD A COMPUTER 101
Date: 10/8/00
By: Rice

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The Motherboard:

   If the CPU is considered the brain, then the motherboard can be considered the body. You basically plug everything into it, like if you're building an android robot. There are a few important concepts you need to understand about motherboards to make the right decision on which one to buy:

1. Front Side Bus (FSB)

    This is the speed in which your motherboard runs at to communicate with the CPU. These days, it can range from 66, 100, to 133 MHz for Intel. All AMD motherboards in theory run on a special 200 MHz bus, called the EV6. However, it's actually only a true 100 MHz bus. For simplicity, we'll just use it as thus.

• Intel Pentium III: Some at 100 MHz, others at 133 MHz
• Intel Celeron: 66 Mhz
• AMD Athlon (Thunderbird): 100 MHz
• AMD Duron: 100 MHz

    Every peripheral in your system will be affected by the FSB. Let's take a 100 MHz motherboard for example. Each "slot" in the motherboard has their own specific MHz rating.

• CPU: Maximum
• RAM: Maximum
• AGP (brown, reserved for graphics cards): 66 MHz
• PCI (white, most commonly found slot): 33 MHz
• IDE (where you plug your harddrives in): 33 MHz

    In order to achieve a 66 MHz rating for the AGP slot, you specify the divider to 2/3rds of 100. That equates to 66 MHz. Obviously then, to get 33 MHz, the PCI & IDE divider is set at 1/3rd of 100.

    In a motherboard officially rated for 133 MHz, the AGP divider would be at 1/3rd and the PCI & IDE divider at 1/4th. I'm pretty sure you can do the math yourself for a 66 MHz motherboard.

2. The Concept of CPU Multipliers (... and overclocking!)

    When you combine the FSB with a multiplier, you get the actual speed grade of that CPU. For example: A 700 MHz CPU that runs on a 100 MHz bus has a 7.0 multiplier. 7.0 x 100 = 700 MHz. Voila! So you see, the "big mystery" behind overclocking / underclocking CPU's is to simply change either the FSB or the multiplier. Both factors are commonly accessable on the motherboard, either via jumpers or the BIOS.

    However, note that ever since the induction of the Pentium II, Intel has locked all of their CPU multipliers on the chip itself. Meaning if you get a 700 MHz P3, the multiplier's locked at 7.0. Attempting to change that will bring nothing. However, what you can do is change the FSB. Let's say we pump it up from 100 MHz to 133 MHz. The result? 7.0 x 133 = 933 MHz!! You get a 933 MHz CPU at a 700 MHz CPU's price. How sweet is that? =)

    The catch is that your CPU must actually have the ability to reach that speed-grade. Manufacturer's mark their CPU's for a reason. A 700 MHz CPU is only guarenteed to perform at 700 MHz. Anything higher is not guarenteed. You might be greeted with a blank screen if you try overclocking too high. In that case, just reset a few times and your motherboard ought to default to its original settings.

    Another catch is that your motherboard must be able to handle the increase in FSB. If it is not officially rated for 133 MHz, and you pump it that high, then the AGP and PCI dividers will not change!! That means your AGP will be running out of spec at 89 MHz and PCI at 44 MHz!! Your peripherals MAY FAIL under those circumstances!

    Further overclocking concepts are beyond the scope of this article. As you can see, there are risks involved that you should understand.

3. CPU Slot Type

    Have you noticed some CPU's come in a small, squarish package, while some are huge, rectangular monsters? Well in this case, bigger isn't better. The former is known as a "Socket" CPU while the latter is known as a "Slot" CPU. Sockets are the way of the future, and according to my CPU recommendation list above, Slot CPU's are as good as extinct. Here's a quick list on types of CPU's and their slot formats:

• Intel Pentium II: Slot-1
• Intel Pentium III (non-Coppermine): Slot-1
• Intel Celeron (non-Coppermine): Slot-1 or PPGA (Socket-370)
• Intel Pentium III (Coppermine): FC-PGA (Socket-370)
• Intel Celeron (Coppermine): FC-PGA (Socket-370)
• AMD Athlon (non-Thunderbird): Slot-A
• AMD Athlon (Thunderbird): Socket-A
• AMD Duron: Socket-A

    In addition, there are also little nifty devices called "Slotkets" that have the ability to convert PPGA / FC-PGA (basically any Socket-370 Intel CPU) into a Slot-1 input. They're handy if you have an older Slot-1 based motherboard, but want to upgrade to a Coppermine PIII.

4. The Core Logic Chipset

    This is probably the most important concept to know when you're purchasing a motherboard. Always find out what chipset it's based on. Once you know which chipset, then you will automatically know the specs that it officially supports. I have listed the most common (and my recommended) chipsets and their specs below:

    If you're confused, try matching the CPU Slot Type with the list I made up earlier. Then you'll see which core logic chipset corresponds with what type of CPUs. You can see that for Intel CPU's you have a lot of choices, but for Athlon CPU's, there is only once chipset worthy of your attention for now: Via's KT133.

    The only terminologies you may be unfamiliar with are the AGP Speed and IDE Adapter. AGP is a slot tailor made for graphic cards. As technology progresses, people are able to engineer even faster AGP slots. That's where the 2x and 4x enter the picture. Don't be fooled though. Real world differences between 2x and 4x are negligable.

    The IDE Adapter is where you plug in your hard drive as it communicates with the motherboard and the rest of the system. ATA-33 capable hard drives can transfer burst speeds up to 33 Megabytes / second. ATA-66 and ATA-100 are the same, 66 MB/s & 100 MB/s respectively. Again, the real world differences are negligable as well. You'll hardly notice the difference between ATA-33 and 100, but they provide peace of mind for the future.

    Lemme try to decipher each chipsets in layman's terms:

• Intel i440 BX:
  -- The most venerable of them all, the BX chipset has been around for over a year already. That's a friggin' millenium in computer time. However, it has withstood all tests because it's the fastest of them all.
  -- Although it doesn't have official support for 133 MHz, lots of people are still running it out of spec because of its excellent performance.
  -- The latest BX boards may have 3rd party implemented features, such as ATA-66/100 to even up the competition.
  -- Ideal board for Celeron users because it's cheaper than the i815e, and overclocking the bus to 100 MHz gives you the most bang for your buck at zero risk as long as the processor can handle it.
  -- Not very future proof.
  -- Best board(s): Abit BX133-Raid, Asus CUBX, or MSI BXMaster
• Intel i815e:
  -- Intel's latest flagship chipset. Contains all the modern features.
  -- However, not much faster than a BX board, if at all. Expensive as well, but guarentees future compatibility plus all necessary AGP / PCI dividers are present.
  -- Best board(s): Asus CUSL2 or MSI 815E Pro
• Via Apollo Pro 133A:
  -- Cheapest Intel chipset. Will probably find this on motherboards in pre-built computers by your local mom & pop computer store.
  -- Slowest as well. But then again, the difference between the fastest and slowest might as well be negligable.
  -- Has some compatibility problems, but mostly been fixed through driver and BIOS updates. But it's just as future-proof as the i815e.
  -- Best board(s): Asus CUV4X (FC-PGA) or Asus P3V4X (Slot-1)
• Via KT133:
  -- The only chipset for AMD processors worth considering.
  -- Best board(s): Abit KT7-Raid or Asus A7V

    Note that Asus dominated the list. However, quality comes at a premium, so don't expect to find Asus boards at the bottom price-wise.

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