Overclocking i7 965

[hiyayhi]

I'm looking for advice on the safe voltage for an i7 965.

 

I have an Intel BOXDX58SO motherboard and 7gb of corsair dominator (3x2 and 1x1gb). 

 

 

Currently I have it at 150 base clock, 1.387V in bios (1.336 in CPU-z), 27x multiplier.

 

 

I have seen multiple tales, some saying that anything over 1.3v is unsafe to just keep it under 1.5V

 

 

 

If you have experience with Bloomfield, what would you suggest?

[jono20]

There's always going to be a correlation between voltage and reliability/longevity. You're probably safe-ish around 1.4 but it will die more quickly than it would if you were at 1.3! At this point I'd just crank the voltage and let it die off so you have an excuse to do a new build

[PhiberOptik]

http://www.overclock.net/t/538439/guide-to-overclocking-the-core-i7-920-or-930-to-4-0ghz

I used this for my 970. Currently at 191x21 at 1.288vcore 1.26v QPI. You should try your luck getting 200x20 stable. You shouldn't need over 1.3v for 4Ghz. I even have a bad chip and got it stable under that but it did take time. 191x21 is fine at listed volts. 200x20 required 1.337v and 1.28v QPI for me. That guide is fantastic other than you will find lots of ambiguity around the PLL, mine is at 1.55v, its one of those settings that's highly dependent on your chip, going down helps some people going up helps other people. Another important note, bios voltage, sensor voltage, and actual voltage are all very different and I recommend you never actually use the max voltage listed in the guide for long, maybe test if it's what you needed and then back down unless you have a meter to check it. I also saw best results when CPU temps were under 65c.

[hiyayhi]

http://www.overclock.net/t/538439/guide-to-overclocking-the-core-i7-920-or-930-to-4-0ghz

I used this for my 970. Currently at 191x21 at 1.288vcore 1.26v QPI. You should try your luck getting 200x20 stable. You shouldn't need over 1.3v for 4Ghz. I even have a bad chip and got it stable under that but it did take time. 191x21 is fine at listed volts. 200x20 required 1.337v and 1.28v QPI for me. That guide is fantastic other than you will find lots of ambiguity around the PLL, mine is at 1.55v, its one of those settings that's highly dependent on your chip, going down helps some people going up helps other people. Another important note, bios voltage, sensor voltage, and actual voltage are all very different and I recommend you never actually use the max voltage listed in the guide for long, maybe test if it's what you needed and then back down unless you have a meter to check it. I also saw best results when CPU temps were under 65c.

Thanks a lot, that gives me a good point of reference to start from

[hiyayhi]

What steping you got ?

Can see with cpu-z

 

http://www.cpuid.com/softwares/cpu-z.html

 

if its a d0 you dont need much volts to overclock while the c0/c1 stepping is much harder to overclock.

 

1.35 max is what intel advices although some c0/c1 stepping require something like 1.40 voltage usualy still not stable so not worth it 3.8 is usualy the sweet spot for c0/c1 4.0 4.2 for d0

I have a C0/C1 chip, currently sitting on 3.6 which is not too bad, I don't think I will get much more out of it unfortunately.

[hiyayhi]

my 920 chip also c0/c1 used be able to do 3.8 @ 1.296v try 200*19 if the temps are reasonable it should be safe anything below 1.35 for that chip should be as long temps are reasonable, my 920 chip could do 3.5 on 1.20

I am getting 3.8ghz at 1.3V with the temps at around 80 degrees in prime. I'm gonna run it over night but it passed a 1h test.

[hiyayhi]

my 920 chip also c0/c1 used be able to do 3.8 @ 1.296v try 200*19 if the temps are reasonable it should be safe anything below 1.35 for that chip should be as long temps are reasonable, my 920 chip could do 3.5 on 1.20

Would you say CPU-Z is a good marker for how much voltage is actually going through the CPU? It is saying 1.289 while it's set at 1.375 in the bios, and I'm not 100% sure what to trust.

[PhiberOptik]

I am getting 3.8ghz at 1.3V with the temps at around 80 degrees in prime. I'm gonna run it over night but it passed a 1h test.

Do not test with Prime95. It is known to damage chips. You should really work on lowering temps before using more volts 80c is not good. Use OCCT, set it to linpack,auto, 90% mem, 2 hours,you can check AVX, I did, I don't think our CPUs have instruction sets for it though, if you can pass 2 hours you're fine. Lower BCLK numbers are often easiest some chips really struggle with 200. You need to enable LLC for QPI and VCORE if you have it, also called low vdroop. Here is a Vdroop article: http://www.masterslair.com/vdroop-and-load-line-calibration-is-vdroop-really-bad