Bladestorm1412

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Dec 22, 2010
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Hi

I am currently overclocking my Phenom II X4 965 (with an Asus Crosshair IV Formula and 8GB RAM). I have managed to get the CPU to 4.2GHz stable (running Prime95 for a few hours). However the progress has now stopped. I dont want to run the risk of frying my PC but I want to see how far I can get the CPU. What is the maximum VCPU voltage i can/should use? At the moment I have it on 1.6V. Thx.
 

logic54

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Oct 5, 2010
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for 4.2ghz? I know the higher the clockthe higher the voltage must be. They always will tell you1.6v is high on any forums Ive encountered. However I think it really depends on the application also what voltage and where. A CPU voltage is different than a ram or video voltage etc.





Logic
 

Bladestorm1412

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yeah in the bios the Vcore numbers are red (i guess just a warning) and it goes up to 1.9 i think. CPU is 52 C, NB is 50 C snd SB is 45 C. I read a forum where someone said the voltage to the cpu cant fry the cpu, its the heat that damages it but I dont know experienced he is.
 

Bladestorm1412

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Dec 22, 2010
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Thx logic54. I am currently running a stress test on 4.3GHz and so far its ok. I am however starting to get a bit nervous about the voltage. The motherboard lets me push it to 1.8V i think but i really dont want to fry the PC.
 

willard

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The BIOS limits should absolutely not be considered recommendations or a guide on what's safe. Just because it will let you do it doesn't mean it's a good idea. The motherboard has to support a wide range of voltages to support different chips, as well as people who are using exotic cooling and can pump the voltage up higher than normal.

Also, too high a voltage can damage the CPU, though the heat as a result of the higher voltage is typically a bigger issue. Normally if your temps are fine, your voltage is probably fine too. The big issue is you can dramatically reduce the lifespan of the chip with excess voltage.

However I think it really depends on the application
Absolutely not correct. Your processor is getting the same voltage regardless of what applications you're using. If the voltage is at a dangerous level, it's just as likely to damage the chip running Firefox as it is BF3 (aside from the added danger of BF3 stressing the CPU more).

yeah in the bios the Vcore numbers are red (i guess just a warning)
Yes, a warning that your voltage is at a dangerous level. Ignore it at your own risk.
 

Bladestorm1412

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Dec 22, 2010
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Thank you willard! I dont think I will increase the voltage anymore. I would rather have a 4.3GHz processor than no processor at all :).
 

loneninja

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Most consider 1.5V the max safe voltage on Phenom II, and usually when you push the voltage too high you degrade the chip and reduce it's lifespan at a noticable rate. I don't run mine past 1.45V.

You'll probably kill the motherboard before the processor, the increase in voltage dramatically raises power consumption and puts a lot of strain on the motherboard. I fried one with a Phenom 9850, part of the board fried up and went from blue to a brownish green while producing a nasty smell. That was over a year ago and the processor still works today in another motherboard.
 

grahamie

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I’d say yes to much voltage but that’s just an opinion try dropping your voltage 2 bumps in the bios and re-run your stress test if still stable drop it again and continue until your unstable then bring it back up 2 bumps and re run stress test to confirm stability and temps. You also may need to increase vdrop voltage as well

My 1090t BE runs 4.586 @1.56v (unstable) and i run (stable) at 4.33 @ 1.54v and my 965 BE ran 4.2 @ 1.475 at 42c max

I have never burn out a motherboard or processor because of voltage but i have over heated a i.m.c in a cpu do to overclocking ram speed