My old AMD Athlon 64 3000+ Winchester I was able to get stable at 2.7GHz on stock air cooling. I tried for 2.8GHz but it was being stubborn, even when I upgraded to liquid cooling.
I was using:
AMD Athlon 64 3000+ 1.8GHz Winchester
DFI Lanparty UT Expert Nforce 4 SLI
2GB Corsair Value PC3200
Ultra X-Ifinity 600W
Currently I've gotten my AMD Athlon X2 5200+ AM2 stable at 3.1GHz from 2.6GHz
Currently using:
AMD Athlon X2 5200+ AM2 2.6GHz @ 3.1GHz
DFI Lanparty UT Nforce 590 SLI AM2
4GB Corsair XMS2 Dominator 800MHz (Could go farther then 927MHz but it's fully stable with 4-4-4-12 timings and seems like it could go farther with same timings)
Thermaltake Toughpower 850W Quad SLI Quad 12V Rails
Can't wait to get (Will be my first Intel build ever):
Intel Core 2 Quad Q6600 (Penryn if I can afford it) and get to 4GHz on liquid cooling
DFI Lanparty UT Intel X38
(Keeping the dominator ram)
EVGA 8800GTS G92 512MB (Step up to 9800GX2 upon release)
Second radiator for my Thermaltake Bigwater 745 (Not using the external radiator, getting a bay radiator)
And then the Dominator fans since the DIMM slots are on the other side of the cpu socket (Currently right next to exhaust fan)
Going to have some fun with my new system.
BTW I was 15 when I hit 2.7GHz on that Winchester. going to be 18 in 8 days and want to become a master overclocker as I'm addicted to the challenge. 