I'll jump in with some components that seem to be the common choice (and
what I would build as an upgrade from my AMD 1600/512MB RAM/GF4 Ti4400 rig):
Asus A7N8X Mobo Deluxe
Popular because of dual channel memory=more speed (need 2 dimms to take
advantage), highly regarding BUILT IN 5.1 sound, USB 2.0 (1.1 compatible),
built in ethernet, built in fire wire, etc. Great deal for $147 (deluxe
model).
AMD 2400+ (best bang for the $ at $175) or if you can splurge go for the AMD
2800+ ($395).
2x512 MB PC 2700 DDR RAM (take advantage of dual channel architecture -
Corsair XMS - $300 total but worth it for the speed - one review showed a
gain of 10-15% between identical processors/video cards due to the mobo and
ram configuration). This RAM will also support 333 FSB processor for a
later upgrade.
ATI 9700 Pro - should really reconsider graphics card, this thing will fly
on your system and driver support has been great ($339). You can run most
games with 4x or 6xFSAA and 16xAnis with little performance loss.
Sound Card - built-in see above.
Since you didn't mention a budget I opted for high end. You can save on
2x256 MB Ram and a cheaper video card (GF4 Ti 4600 128 MB RAM).
--
Joe M.