Core i7/X58 Overclocking Thread

[eva2000]

According to intel (bit-tech) article vdimm >1.65v is allowed as long as vdimm with within 0.5v of cpu vtt or what asus termed qpi/pll volts. So if you went by cpu vtt max of 1.35v, then vdimm 1.85v would be safe. But i'm seen some folks throuh max cpu vtt specs of 1.55v ?? so then vdimm of 2.05v would be max. Hopefully, someone clears this up eventually heh

[Extelleron]

This is what I have gotten so far w/ Core i7 920 + P6T Deluxe.........

BIOS settings:
CPU Voltage: 1.33750V (LLC disabled)
Uncore Voltage: 1.33750V
PLL Voltage: Auto
Memory Voltage: 1.62V



Passed 199 iterations of Linpack 64-bit, definitely good enough for me. There is an error with the latest LinX that makes it stop before completing though so that is why it shows 199/200.

3.8GHz @ 1.264V seems pretty good but 4.0GHz (191x21) is a no go so far. With 1.4V in BIOS (1.320V under load) I get BSOD within a minute or so.



$150 G. SKILL DDR3-1333 = 18 GB/s is pretty good IMO.

[ReverendMaynard]

According to intel (bit-tech) article vdimm >1.65v is allowed as long as vdimm with within 0.5v of cpu vtt or what asus termed qpi/pll volts. So if you went by cpu vtt max of 1.35v, then vdimm 1.85v would be safe. But i'm seen some folks throuh max cpu vtt specs of 1.55v ?? so then vdimm of 2.05v would be max. Hopefully, someone clears this up eventually heh

That is correct eva. Keep a 0.5v buffer between the two voltages but that really only applies to the upper limits. Those folks going 1.55v cpu vtt, even if they're keeping the 0.5v buffer are rolling back the lifespan rapidly on their cpu.

But hey, that's what extreme everclocking is all about right?

[SteveRo]

Reverend - very good - qpi of 1.55 is a bad thing - got that.
What do you consider to be a safe qpi v for 8-12 hrs per day - and if CPU can be allowed die in say ~3 years?

[ReverendMaynard]

Reverend - very good - qpi of 1.55 is a bad thing - got that.
What do you consider to be a safe qpi v for 8-12 hrs per day - and if CPU can be allowed die in say ~3 years?

Personally, I take Intels maximum and apply the rule of +0.1v. Intels max is 1.35v, my max is 1.45v for long term regular use. Really depends on how hostile that cpu's environment is. Cooling is huge of course, but also how much load and what kind of load. If I were to fold on this rig, 100% HT enabled I would definitely stick with Intels max if I had a 3 year window.

[Xello]

You can follow Reverend's advice but the truth is no one can answer your question, not for another 3 years

There are people who also say 1.55v VTT, even 1.65v is fine and will not degrade your cpu as long as you keep the 0.5v max between VTT and vdimm. Some people are needing this to get their old ddr3 2v+ kits working at stock.

You need to make up your own mind, or just go with someone else's mind i guess. Personally i don't want to go over 1.45v vcore and 1.45v VTT right now, because i don't need to for the clock i want

[ReverendMaynard]

You can follow Reverend's advice but the truth is no one can answer your question, not for another 3 years

There are people who also say 1.55v VTT, even 1.65v is fine and will not degrade your cpu as long as you keep the 0.5v max between VTT and vdimm. Some people are needing this to get their old ddr3 2v+ kits working at stock.

You need to make up your own mind, or just go with someone else's mind i guess. Personally i don't want to go over 1.45v vcore and 1.45v VTT right now, because i don't need to for the clock i want

Absolutely. I just play a bit conservative but still over Intels maximum. It's done well for me in the past so I ride it.

[Xello]

Same here, and if the vast majority of us are getting desired 24/7 settings between 3.8 and 4.4ghz with these voltages then there's no real need to go over them, unless benching or you have a really bad chip

[Hornet331]

Personally, I take Intels maximum and apply the rule of +0.1v. Intels max is 1.35v, my max is 1.45v for long term regular use. Really depends on how hostile that cpu's environment is. Cooling is huge of course, but also how much load and what kind of load. If I were to fold on this rig, 100% HT enabled I would definitely stick with Intels max if I had a 3 year window.

3 years? I dont plan to keep my current Ci7 longer then one year (westmere release)

[ReverendMaynard]

3 years? I dont plan to keep my current Ci7 longer then one year (westmere release)

I'm on a 3 month cycle and have been since the 939 Opty's

[Tobit]

I'm on a 3 month cycle and have been since the 939 Opty's

Heh, I'm upgrading to an i7 from a Celeron 331.