Originally Posted by The Sandman;12078287
I've found that when one or two workers fail (rather than BSOD) and it shows a rounding error that it is usually a sign of either cpu/nb voltage or ram voltage being a little low. Just a little unstable yet is all.
I just ran Prime95 all day today and got a rounding error on one core after 2 hours. The other core was still running strong when I got home (10 hours). I only have the CPU OC'ed to 3.4GHz (@ 1.4v), which is kind of a high voltage for that mild OC. The RAM is only clocked at 1512Mhz at 1.6v, so I am thinking I have some crappy RAM. It passes memtest but it just doesn't like Prime95.
Another few points I'd share is to
1st. OC the cpu first (isolated), and stabilized w/12 hrs of prime95
2nd. OC mobo using HTT (ref clock) (isolated, while maintaining near stock CPU, NB Freq, HT Link Speed, and Ram Freq)
Don't I have to do both at once? I don't have a black edition CPU, so in order to OC the CPU I have to OC the reference clock.
At any rate, I did a reference clock OC when I first got the board. I turned every multiplier to its lowest setting and was able to achieve a 280 reference clock before crashing -- and this was with everything at stock voltages.
But I guess I will start from scratch again and begin with the CPU ref clock.
After a couple of hours of CPU overclocking, I have found that I can get it to 3.5GHZ at 1.425v. I can get it to 3.7GHz at 1.5v. (Both of these clocks will pass a Prime95 Blend test for about 15 minutes).
I checked AMD's website and the max Vcore for this proc is 1.425v. So, there is no way I am running it at 1.5v for any extended period of time. When people say that AMD says 1.5v is safe, they are talking about the QUAD core processors. Since this is a dual-core, the max voltage is 1.425 according to AMD.
My temps at 3.5Ghz (1.425v) are about 36C under a Prime95 load. At 3.7Ghz (1.5v), I am at 40C under load. So temps are not an issue. My cooler is pretty much a clone of the Arctic Freezer 7 (plus I have lapped it). Still though, it doesn't matter how low temps are -- over-volting can still kill a processor even under ice cold conditions.
At any rate, I guess it was not my RAM after all. All the BSOD's and rounding errors disappeared after I increased the Vcore to these insane rates. It seems that my CPU has to have a LOT of juice to OC to any decent amount. I guess I am not as lucky as a lot of people who say they get 3.7GHz with just a single bump in Vcore.
I think I will drop it back down to 3.5Ghz (@1.425v) for my 24/7 OC. Now I need to figure out how to get the CPU-NB overclocked. Right now I am running it slightly under stock. After that I will mess with RAM timings, which I am sure I will need help on.Edited by thiussat - 1/20/11 at 8:11pm