If you are building your own system kudos to you. You can consult this guide about how to squeeze the most from your computer. I will explain the systems I often implement in order to produce the fastest computers. The tricks I use are proven techniques I have developed over the past 10 years to improve performance.
Taking advantage of DDR memory
DDR memory can be made to perform up to 15% better when installed on a dual channel motherboard if you install the memory in pairs. You simply need to buy two sticks of DDR memory (preferably match pairs) and install one into each memory channel. Consult your motherboard manual on proper procedure. This is a simple way to milk some extra speed out, overall it won’t seem like much but internally, and combined with other optimizations it will really lead to much better performance.
RAID
RAID system can effectively double your hard drive transfer speeds, but they can also increase your chances of hard drive failure and loss. There are however effective ways of implementing RAID without fear of losing your data. Primarily I am talking about RAID 0 data striping here. Check your motherboard documentation to find out if it can support raid, and how to install it.
The first thing you need to know about reliably implementing a RAID stripe is that I highly recommend using three hard drive for reasons I will discuss later. The second thing to know it that you really need a clean install of the O/S when installing a RAID system. Next make sure that when you install your RAID system that you only attach the two drives for boot partition of the raid system, and your CD/DVD drives when installing the O/S. If you have other hard drives attached it will bump your RAID stripes letter back from C: to D: or further back in the alphabet which causes problems with a slight few programs. If you install the raid drive independent of other drives it will assign C: to the RAID drives, and bump the subsequently installed drives letters back. Last in Windows XP as the installation program launches you will need to hold the F6 key when prompted on boot in order to install the driver for your RAID stripe.
Now the reason for three drives is this; the third drive should be a large drive enough to make backups of your RAID stripe. This will insure that you don’t lose your data in a crash or if a drive fails. The other reason I really recommend a third drive is so you can put the O/S swap file on it which will significantly improve system performance. If you use this system just make sure to belt yourself in, it is extremely fast on all hard drive intensive operations like system boot.
Video Card Chipsets
In a very fast system it is important to have a very fast video card as well. Most good modern video cards carry a great deal of the load that would otherwise fall to your processor in certain applications like video games. A good card will improve video quality, and speed while also taking load off your processor leaving it free to handle other thing like audio, decoding, AI, background O/S procedures, etc.
I will not be detailing the features of each GPU, however I will give you some pointers on general ratings for GPUs. On the Nvida side of the equation you have several lines of GeForce cards the GPU feature set generally being the first number in there designation. The following three numbers can generally be converted into relative performance. For example a Geforce 6200 is a base on a Geforce series 6 GPU and will generally out perform a 6100, and under perform a 6800.