You don't need to know a whole lot to build a great AMD based system.  On the other hand, a few tips will ensure that you get the maximum performance, upgrade flexibility, and cost savings.  There are several areas to focus on when building a computer; video, memory, storage, a cool case, etc.  This article will focus on the core (the CPU) and it's immediately related components.

AMD socket 939 provides an excellent variety of processor chips.  The features to look  for are first processing speed, second L2 Cache, and third FSB.  There are lots of other things to consider, but these are the most important.  It is important to find a processor that is running at 1.8ghz to 2.4ghz.  Why not faster?  Simply put, the AMD chips tend to work faster than their rated speeds and the prices seem to climb dramatically with rated speeds above 2.4ghz.  Second is L2 Cache; this is the second place the processing core will look for the data it is currently working with.  To alleviate data bottlenecks to the processor, and take full advantage of the processor speed you have paid for, make sure you have a 1mb L2 Cache.  Finally, the speed of the FSB (front-side bus).  Similar to the issue with L2 Cache, you do not want to create a data bottleneck.  FSB speeds of 2000mhz are optimal.  Some highlighted products in the AMD socket 939 family are the Athlon 64 3700 and Athlon 64 X2 (dual processing core, 1 chip) 3800.  These two chips are very affordable.  In fact they are the least expensive Athlon 64's to carry a 1MB L2 cache.  Also worth mentioning are the Opteron 146 and 148 which are recognized for performing just below 3ghz which is well beyond their respective 2.0 and 2.2 rated speeds.  Additionally, they are the least expensive Opterons to employ a 1MB L2.  The dual core Opteron 165 has recently dropped in price and features a 2MB L2 Cache.

A socket 939 motherboard is a beautiful thing.  There are some things to identify with this component.  First, compatibility.  Although you can put an 939 Opteron chip in any 939 motherboard, the manufacturer technically holds the keys as to whether this is an approved compatiblity.  My research has identified the MSI K8N Diamond Plus as the least expensive, mainstream board that is compatible with Opteron chips according to the manufacturer.  This is a wonderful board too.  Here are some other motherboard features to be aware of.  The first, for pure processing horsepower, is the amount and speed of the RAM memory it supports.  Expandable to 4GB is good.  Right now, the industry recommends 2GB and 1GB is pretty much the minimum.  You can definately function with less, but you will have a noticeably sluggish system.  The second feature is for the gamers out there.  Video interfaces such as AGP have just about reached their cap.  If you plan on upgrading your video card, or buying one of the top performing cards right now, you will want to use a PCI express 16 slot.  If you are a serious 3-D gamer, you should also consider a motherboard that is either nVIDIA SLI or Crossfire ready.  These motherboards utilize two PCIx16 slots and allow you to have two high-end graphics cards working in concert (the graphics cards must be SLI or Crossfire ready).

The final item to consider when "Maximizing your AMD CPU experience" is cooling your chip.  Your processor chip puts out a tremendous amount of heat which slows processing speed significantly.  The best thing you can do to increase the performance of your processor is to upgrade the stock heatsink and fan.  There are several products available, but again the best performance for the money will be a pure copper heatpipe attached to a very efficient fan. 

Whether you are an experienced builder, or this is your first project, you will be pleased with the performance of the products I have described and you can have confidence that they will work well together.