Who has an answer for this strange anomaly?

[db2431]

So I bought a new system, 6400, p5b-e,2GB (2x1GB) CorsairTwinX XMS2, DDR2 PC2-6400 (800), 240 Pins, Non-ECC Unbuffered, CAS 4-4-4-12, EPP(2.1volt), an 8800gtx and a thermaltake toughpower 650watt. So I go to overclock i set to 401 x 8 for 3.2ghz, seems to run fine in windows and gaming at 1.43 volts.I try 425 x 8 for 3.4 ghz 1.47v, again seems to run fine.Going to 438 and any voltage and 3d tests freeze the system.So i go back to 3,4 ghz, go in to windows and run orthos and it fails within 2 minutes, try again, 3 minutes fail, and again 3 minutes then fail.I spend hours fiddling with settings till i lower my vdimm from 2.1( the rating the ram should run at ) to 2.0 and Voila! No errors?Anyone have any idea why putting the ram to 2.0volts, 0.1 lower than it should run gives no errors?It wont even post at 3.5ghz at 2.0 volts on the ram where 2.1 did.Also putting ram down to 1.9 and the machine doesnt even post at 3.4ghz.Also setting my ram to its rated 4-4-4-12 wont even show post, so I have to leave it at auto on 5-6-6-18, All very confusing! If someone has an answer that would be great!