Vcore for unlocked phenom II x4 at 2.9 ghz?

[-Slacker-]

So I managed to unlock my athlon 2 x3 435 into a phenom 2 x4 B35 and now I'm I'm afraid to do stress testing because I don't know if I even got the voltage half right.

I fiddled with the voltage control for a bit and then had to settle on something like 1.415 V because that's around what cpuz was indicating.

But now I can see the core spiking to 1.448 (in cpuz) and I'm like oh poop...

What's more confusing is that I could find examples of overclocked phenoms 2x4s running at 1.375 volts - although I'm guessing that's just the stock voltage ..?


Should I decrease the vcore then?

 

[MarkLuvsCS]

I was running my Phenom II x6 @ 4ghz @ 1.45v, it stayed under 60c under load with 2 massive 120x38mm fans on an H50. I've never had quiet systems so it wasn't noticeable with headphones to me, but I know the noise would have been too much for others.

 

[SlowSpyder]

That voltage is safe. It is more than it should need for just 2.9GHz, but it isn't an unsafe voltage. My only concern is if you have a lower end motherboard, that voltage may up the power draw. At least I think increasing the voltage at a given speed would do so.

 

[-Slacker-]

Well that's a relief

OK my next beef is with the memory timings.

They are now operating at 9-12-12-30. Could I get BSOD from that and should I change them to 9-9-9-24 or something? (kingmax PC10700 665mhz)

 

[pelov]

It depends on what your RAM is and what the recommended timings are. Go into the BIOS and change them to what the sticks recommend and then run some stress tests.

Are you planning on overclocking the CPU? If not, you can drop the voltage to ~ 1.35v and maybe even lower. You should really try to stay beneath 1.45v if you intend to overclock it. though.

 

[-Slacker-]

Apparently the timings are 9-9-9-27, not 24 ...

I'm going to leave the cpu vcore as it is until after I do some stress testing.

 

[superccs]

At 3ghz you should be around 1.35V

 

[-Slacker-]

But why does gpuz show values as high as 1.448?

Also, should I take into account that the CPU may still have some factory defect that makes it waste power and run at high voltages in it's unlocked state? 'Reason being that it's likely a defective phenom that didn't quite cut it as a phenom.

 

[KingFatty]

Two things - you can 1) start incrementally increasing the frequency for better performance, to see how high you can go at that voltage before becoming unstable; or 2) start incrementally decreasing the voltage for better power savings/efficiency, to see how low you can go before becoming unstable.

Either way, mess around, it's fun finding the limit then pulling back and feeling like you found the limit of your chip and eliminated that uncertain feeling:

 

[SlowSpyder]

For the record, OP, I run about 1.49v for 4.03GHz on my Thuban. You should be able to run 2.9GHz at less voltage, but that voltage won't hurt the CPU.

 

[-Slacker-]

Mine goes almost as high in prime95 ... 1.47v ... not sure what to make of that. Is the voltage that's displayed in cpuz/speedfan/etc dependent on the voltage that you tweak in bios, or does it show the same values, no mater what bios is set to?


edit: Ok I guess it's the former. I lowered the vcore form 1.415 to 1.375 and the cpuz values followed suit, from 1.47 to 1.43 ... it looks like cpuz adds .5 ~ .6 to the readings for some reason.

Also the temps decreased by 3c (which I'm not sure I can trust since it seems temperature monitoring software doesn't take kindly to unlocked cores and doesn't read the "core" temperature value for most people).