X2 555 Unlocked to x4 @4ghz, stability

[dave343]

I unlocked my 555 to X4 and managed to clock it up to 4ghz but I have a question about stability. @3.6 to 4ghz I can run Cinebench 11.5 (seems to stress the CPU 100%), and Future mark Vantage, both complete successfully multiple times over. Now if I try and run prime it fails immediately (PC doesn't reboot/crash) Prime just says it failed off the bat and can't continue.

IF I run the 555 as a normal dual core, I can achieve 4ghz@devault V and Prime completes successfully.

My question is, since I can unlock to x4 @4ghz and successfully run Cinebench 11.5 (maxes CPU) and Future Mark Vantage, should that be enough to say it'll run games OK? I know Prime fails, however it's not like I bought the CPU to sit there and run prime... Cinebench 11.5 seems to max the CPU out, so I can't see why it wouldn't stay stable in games? No/Yes? Thanks in advance.

 

[OvrClkr]

4Ghz on a B55 is highly unlikely to be 100% stable unless you can keep the CPU at 52c (or lower) under load. The CPU cooling is whats going to determine how far you can push the CPU w/o crashing. If it runs fine in Vantage/Cinibench but it crashes when primed the that tells you that its not 100% stable. When running your CPU as a dual core it will run much cooler and in-turn run at a higher clock speed w/o crashing. Try lowering the clock to 3.9Ghz and re-test.

3.8Ghz (x4) is more than enough CPU power for any game, no need to push it any further. My B50 can do 4Ghz stable but since I do not need that much speed/heat I just leave it at 3.8Ghz.

Also what voltage did you use for a 4Ghz overclock?

 

[Guest]

for a stock 5850 3.4 ghz is all you need from a phenom II x4 so take that into consideration with your OC