First time OC cpu using option in BIOS?

rlorenzo1

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Oct 20, 2011
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I have a q8400 on a asus p5n-e sli mobo and maxorb cpu fan. Am interested in OCing the cpu. Ive been doing alot of reading and still not confident about doing it all manually just yet.

Well there is an option in my bios to OC the cpu to 5%,10,15 and 20%. I started with 10% and everything seemed fine with temps not rising above 50c. I tried 20% and it wouldnt boot up. I tried 15% and everything seemed fine temps around 50c under load. However I was playing crisis warhead to see how it would respond and after some intense play my PC crashed for a hard reset.

My question is simple. Is it safe to OC using this option in bios? I know the more experienced choose to do it manually but Im just not confident enough. Why wouldnt my PC boot from a 20% OC? Because ive heard that you can safely OC this cpu to around 3.4ghz. The 20% oc option brings it to 3.2.

my specs
q8400
asus p5n-e sli
4g ram
gtx560ti
nzxt xion case with 5 fans incl. thermaltake maxorb cpu fan.
600w psu
win vista 64
 

christop

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I had the same problem with the 20 percent option. I think it doesn't get enough voltage to boot. You can get 4ghz from your cpu if you have a good cooler. You have to bump the fsb a little at a time and then you will have to increase you volts to the cpu and the nb. Try google and look for ocing a q8400.
 
You are probably not going to get a stable under load 4.0 GHz from a Q8400. The internal multiplier just isn't high enough. Stock, a Q8400 runs at 2.66 GHz (333 MHz X 8). The upper FSB limit of an nForce 600 chipset is about 450MHz. That mean that the most you can reasonably expect is around 3.4 GHz.

Unless your Q8400 has a relatively high VID, 3.2 GHz should be attainable. The problem is that the X% options in the BIOS still depend on automatic settings. Your problem could still be not enough voltage or bad memory settings.
 

rlorenzo1

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Oct 20, 2011
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Ok thx for the advice. So now I am thinking that I need to tinker with voltage setting and memory. I would be more then happy with a stable 3.2

Any advice on how to go about this for a noob? As i stated I have only used the overclock option in bios to do any OC. So now am I looking at changing that to manual and going in and messing with voltage and memory settings?

Is there any places of info you could point me to for this? What kind of memory and voltage settings am i looking at for this (3.2) kind of oc?

thx