BD7II + P4 1.6a stopped overclocking

I've been running an Abit BD7II-RAID and P4 1.6a @ 2.4 ghz since June with no problems. I have it wirewrapped and the core voltage is reported as about 1.69 V. Just a few days ago, I started getting lots of instability, and now most of the time XP won't even boot. If I run at 2.1 ghz, Prime95 crashes after a few iterations. The only way I can get XP to boot and run Prime95 stable is running it at 1.6 ghz (well, maybe slightly higher but its not worth talking about).

I am using a generic 250W power supply. I've measured the voltage of the power supply straight from the MOLEX connectors with a DMM. When idle, my 5V rail is at 5.1V and my 12V is at around 11.9V. When running Prime95 at 2.1ghz (before it fails) my 5V is at 5.1V and very stable while my 12V rail is at about 11.75-11.8V. I can't measure my 3.3V rail directly but Hardware Monitor tells me it's about 3.18-3.20V. These all seem to be reasonable voltages..

Other hardware I have is a single 5400 rpm HD, a GeForce 2 which is non-overclocked, a Santa Cruz, and a NIC.

So, I would jump the gun and say it's the power supply, but my voltage readouts seem pretty good.

I tried upgrading to the latest BD7II BIOS but that didn't do much. Also I'm running a fresh install of XP.

I don't think it's temperature related because I reapplied the silver thermal grease on my retail HSF. Also, after I started having stability problems, I pulled my case off and have a panaflo blowing right on the heatsink, and it's cool to the touch yet not any more stable than with my case on.

Any tips or suggestions would be much appreciated! Otherwise I might head over to Best Buy and get an Antec 330W TruePower to see if that fixes my problem. And hope they have a good return policy in case it doesn't!

Oh also I am using 2x256 Corsair XMS3000 modules. I tried all combinations of pulling one out, running the memory slower, etc and that didn't help so I don't think that's the problem.

Another addendum, I tried increasing the core voltage more, and it reset my CPU settings. I tried reducing the voltage and it wouldn't even make it past the BIOS screen.

Sounds like you are frying the CPU to me..... I would try to sell it as long as it works and get a new one....

Other people have had similar problems with their P4s "breaking down" when running them at or higher than 1.7 vcore settings for long periods of time too. Try running it at 1.5 vcore for about a week. Then try overclocking it again, but this time limit your overclock to what the 1.5 vcore will allow. It might overclock again someday if you're fortunate