Yeah, I put together x86 boxes now and then. All the ones I've built recently, both for friends and myself have been perfect. Flawless workhorses that are rock solid (except when you load Vista and start running into driver issues...)
When spec'ing a system, I typically go through the following steps:
1) Choose CPU. Honestly, both AMD and Intel make great CPUs. Pick one in your price/performance range. When making a determination, I always avoid the low-end models that have reduced cache. The performance hit is greater than the price reduction. If you need to go cheap, skimp on clock rate, not the cache.
2) Choose motherboard chipset. I like to stick with Intel and AMD chipsets (depending which CPU you want, of course...) I'll occasionally stray to an nVidia chipset, and have had luck with those, as well. I'm always wary of SiS and VIA. Driver support is critical and sometimes lacking for those two, causing performance and stability issues.
3) Choose motherboard brand. More expensive isn't always better. I typically stick with a manufacturer that basically just implements the reference designs without doing too much "innovation". (Innovation is great and all, except it plays hell on support and stability.) Gigabyte has been a favorite of mine the past few years. I haven't had a single issue with one, yet.
4) Don't skimp on the RAM or power supply. Both of these are kind of invisible and generic parts. But buying crap ones of either can really kill system stability. Check Tom's hardware or whatever, and pick yourself a model out of whatever the current top brands are. I like Antec for power supplies and OCZ for RAM, but I'm sure any of the top brands there should give good performance.
And that's pretty much it. Following these guidelines you'll probably end up paying about as much as purchasing a complete system somewhere, but you'll sure have a lot nicer rig that won't die when you need it.
