I have almost the same setup as you hehe.
AMD 3000+ Winchester
MSI Neo2 Platinum
1 Gb Corsair XMS PC 3200
XFX 6600GT agp
I will try overclocking it past 2.4ghz, It has been just randomly rebooting in the middle of a high-load program. I tihnk my ram is running too high I dont have it set to any dividers, this is the top choice in the Cell > Ram settings in the bios right? So far my temps are fine with 35C idle and around 42C underload with a XP-90. I just need to do alot of testing, sometimes it wouldnt go past the POST and froze before the windows load screen.
Have you guys bumped up the voltage unless the comp wasn't booting? Also anyone else experience random reboots while overclocked? My CS:S Sometimes freezed up or comp just rebooted after a few minutes. Its not the PSU I have an Antec 400W, and not that many components.