Lots of good suggestions... Thanks to all for the input.

To clarify a little, I should state that I'm not terribly concerned about noise... I mean, all things being equal, I'd like a quieter PC, but it's not at the top of the priority list. I did look very seriously at Shuttle PC's six months or so ago, and now that they support AMD with the nForce chipset, it's very appealing... Since I don't follow this stuff closely, I missed seeing that Shuttle now does AMD boards. I'll be stacking my current plans (new MB, CPU, RAM inside my current PC, current MB, CPU, RAM get put into 2nd case) against the prospect of bringing a Shuttle XPC into the mix.

After doing a little research, I've seen lukewarm reviews of the Barton chips. It only looks like the extra L2 cache helps you out to the tune of 6 or 7% in most applications, a factor which could easily be exceeded by overclocking. I do agree that an XP1700+ against an XP2500 is no contest, but it's also almost $100 in price difference. Right now, I'm leaning towards an XP1700+ or XP2100+ Thoroughbred B as the CPU.

The Abit NF7-S is definitely the mobo I'll get unless I go with the Shuttle. The Shuttle adds in an interesting caveat, which is that it's got the built-in video, along with built-in LAN, built-in audio.. There are pluses and minuses involved there, which I'll stack up against each other this weekend, probably. The one area the Shuttle will almost surely suffer in is the overclockability, and that's something I'll have to factor in.

I haven't really focused in on cooling yet, that's something I'll have to consider unless I go the Shuttle route... Lots to think about this weekend.

Anyway, I'll post some more later in the weekend when I've had a chance to do some comparison. Thanks for all the hints, folks.