24/7 voltages for the i7 and x58

[onemorekornkid]

I'm curious to know what the ceiling for a 24/7 Core and CPU VTT voltage would be. Right now I'm on the brink of 4 ghrz but for some reason even though I can get prime and memtest stable at 200x20, my games will crash Right now I'm running at a Core Voltage of 1.5 and a VTT voltage of 1.45 at 3.8 ghrz, and my temps are great. The CPU and the NB Temps never go above 50*C. What would you suggest?

[ReverendMaynard]

Those are the voltages that I use for 4.5ghz on my C0/C1 920.....there is a point where too much is just as bad as not enough and it looks like your at that point. 3.8ghz at those volts is something to think about; even the crappiest examples I've seen can do 3.8ghz HT with out allot of tweaking voltage wise.

[Mpetrosino]

try 1.4vcore. then work your way up from there.

[Splave]

I'm curious to know what the ceiling for a 24/7 Core and CPU VTT voltage would be. Right now I'm on the brink of 4 ghrz but for some reason even though I can get prime and memtest stable at 200x20, my games will crash Right now I'm running at a Core Voltage of 1.5 and a VTT voltage of 1.45 at 3.8 ghrz, and my temps are great. The CPU and the NB Temps never go above 50*C. What would you suggest?

I run it stock for gaming i920 1920x1080

[ReverendMaynard]

A list of components and other voltage, ram multi, QPI multi and anything else would help allot.

[PRJ]

I run 3.85 @ 1.38XX Vcore / 1.26 VVT / 1.665 Vdimm and I have a crappy C0 Version

[onemorekornkid]

Yeah, it does seem that those are pretty high voltages, but it seems like anything lower instantly causes a crash when I run prime 95. Maybe I'm doing something wrong?

These are my main components:

DFI x58 t3eh8
i7 920
OCZ Gold (running at 7-7-7-24)
PC Power and Cooling 920 watt

Current settings are:
bclk: 190
multiplier: 20 (turbo currently off)
qpi frequency: auto
dram frequency: bclk*08
uncore frequency: bclk*16

vcore voltage: 1.5
cpu vtt: 1.4
dram voltage: 1.65

I made sure first my ram was stable, so I ran tests with memtest at 200 7-7-7-24 and it;s stable for 24/7, so I don't think my ram is my bottleneck, but maybe the timings are too tight? I don't know, I'm still getting used to the x58 setup

I also just tried lowering all of my main voltages down .1 and Prime95 immediately froze.

Any suggestions?

[Longbow]

Try running (21x191) or (19x211). my 920 needed high voltages with 20x200 and would be unstable. 21x191 only needed 1.4v and is rock stable

[ReverendMaynard]

Yeah, it does seem that those are pretty high voltages, but it seems like anything lower instantly causes a crash when I run prime 95. Maybe I'm doing something wrong?

These are my main components:

DFI x58 t3eh8
i7 920
OCZ Gold (running at 7-7-7-24)
PC Power and Cooling 920 watt

Current settings are:
bclk: 190
multiplier: 20 (turbo currently off)
qpi frequency: auto
dram frequency: bclk*08
uncore frequency: bclk*16

vcore voltage: 1.5
cpu vtt: 1.4
dram voltage: 1.65

I made sure first my ram was stable, so I ran tests with memtest at 200 7-7-7-24 and it;s stable for 24/7, so I don't think my ram is my bottleneck, but maybe the timings are too tight? I don't know, I'm still getting used to the x58 setup

I also just tried lowering all of my main voltages down .1 and Prime95 immediately froze.

Any suggestions?

What's the stock frequency of that OCZ ram? Is it 1333 or 1600? OCZ Gold PC312800 is rated at 8-8-8-24, no Gold series that I can see on the OCZ site are even rated to run 7-7-7-24 at 800mhz. 190 would be 760, but that's still way tight.

Drop your DRAM multi to 6x, keep uncore at 16x and set the timings according to the manufacturers specs until you know what you're doing

[onemorekornkid]

That's a good point. I just figured that I would OC the ram before I OC'd the CPU just to get that out of the way. Regardless, I took the clocks down to manufacturer's standards and it doesn't really seem to show a noticeable stability increase

Right now I'm going through the basics and trying to figure out what combination of what work best, but I'm really starting to think that I just got a power whore of an i7

[onemorekornkid]

"my 920 needed high voltages with 20x200 and would be unstable. 21x191 only needed 1.4v and is rock stable"


That's the same exact situation I have. I'm gonna try that some more after work. I'll post some results later.

Thanks for all the help guys!

[Longbow]

yeah. there are posts in forums saying there are some 920's that have issues with either 19, 20, 21 multi's. seems like 20 is the most common.

[icecpu]

Yeah, it does seem that those are pretty high voltages, but it seems like anything lower instantly causes a crash when I run prime 95. Maybe I'm doing something wrong?

These are my main components:

DFI x58 t3eh8
i7 920
OCZ Gold (running at 7-7-7-24)
PC Power and Cooling 920 watt

Current settings are:
bclk: 190
multiplier: 20 (turbo currently off)
qpi frequency: auto
dram frequency: bclk*08
uncore frequency: bclk*16

vcore voltage: 1.5
cpu vtt: 1.4
dram voltage: 1.65

I made sure first my ram was stable, so I ran tests with memtest at 200 7-7-7-24 and it;s stable for 24/7, so I don't think my ram is my bottleneck, but maybe the timings are too tight? I don't know, I'm still getting used to the x58 setup

I also just tried lowering all of my main voltages down .1 and Prime95 immediately froze.

Any suggestions?

Is it your CPU VTT way too low, I think default is 1.80
need someone to confirm

This is what I read at one of the review

CPU PLL voltage (phase locked loop - a feedback control system that automatically adjusts the phase of a locally generated signal to match the phase of an input signal). This voltage used to be very important for successful overclocking of quad-core LGA775 processors, and is still important for overclocking Core i7. The nominal setting for this voltage is 1.8V, but Intel allows increasing it up to 1.88V without any risks for the processor.

[Kougar]

What's the stock frequency of that OCZ ram? Is it 1333 or 1600? OCZ Gold PC312800 is rated at 8-8-8-24, no Gold series that I can see on the OCZ site are even rated to run 7-7-7-24 at 800mhz. 190 would be 760, but that's still way tight.

Drop your DRAM multi to 6x, keep uncore at 16x and set the timings according to the manufacturers specs until you know what you're doing

That's a good catch, Gold kits aren't rated for 1600 7-7-7-20 timings, but OCZ does sell Platinum 1600MHz 7-7-7-24 kits. In fact they are cheaper than the Gold kits when I bought mine. Mine's been running great at ~1638MHz 7-7-7-16 1.66v. I'm slowly being converted away from Corsair.

Is it your CPU VTT way too low, I think default is 1.80
need someone to confirm

This is what I read at one of the review

Trying to kill his CPU?

CPU VTT is the CPU QPI bus voltage. Stock is 1.20v.

CPU PLL is an entirely separate setting... Stock is 1.80v.

Those voltage seem pretty darn high for 3.8GHz... unless it is a C0. My CPU is definitely below average D0 but it requires 1.36v (Loadline Calibration enabled), VTT of 1.3v, and IOH of 1.2v.

[cadupradoo]

lol Really, don't set CPU VTT at 1.8V

But maybe a little more CPU VTT wouldn't hurt... I run mine C0 (already sold to get a D0) at 1.44V and VTT at 1.5V to get 4.2GHz.. For benchs i push my vcore up to 1.64V and vtt to 1.61V...

i7's have problems with even multipliers... always keep then on odd multi. 19x or 21x is the way to go..

And yes, you'll problably have too much vcore. You can try setting 1.45Vcore, 1.4V CPU VTT 1.6V on vdimm and all other voltages on auto.

Don't forget to set Uncore multi at 2 times the ram only. Not more than that. MCH Strap can be set to 1600MHz as well, but I would try on auto first.

Try this.. I remember once I had problems to get 4.0GHz.. started all over again, and bam, with a lot of voltages on auto, I got 4.0 easily...

Best Regards

[ReverendMaynard]

That's a good catch, Gold kits aren't rated for 1600 7-7-7-20 timings, but OCZ does sell Platinum 1600MHz 7-7-7-24 kits. In fact they are cheaper than the Gold kits when I bought mine. Mine's been running great at ~1638MHz 7-7-7-16 1.66v. I'm slowly being converted away from Corsair.



Trying to kill his CPU?

CPU VTT is the CPU QPI bus voltage. Stock is 1.20v.

CPU PLL is an entirely separate setting... Stock is 1.80v.

Those voltage seem pretty darn high for 3.8GHz... unless it is a C0. My CPU is definitely below average D0 but it requires 1.36v (Loadline Calibration enabled), VTT of 1.3v, and IOH of 1.2v.

Indeed. I know a lad using those same sticks as you and pulling off killer clocks.

I have a C0 and it doesn't take anywhere near those voltages to get to 3.8ghz. I run linx 20 pass at 3.7+ at 1.2v vcore, 1.175 QPI VTT with HT on. But it sits at 4.3ghz 8x/18x HT off at 1.408v, 1.375v QPI VTT and again...rock stable.

I think the OP needs to list his settings if he wants any decent help without all the guessing.

[bluehaze]

I've had 3 different 920's first one needed 1.5 volt for 4.0 ghz, second one needed 1.38 volt for 4.2 ghz, third one needed 1.215 volt for 4.2 ghz. Temps are always the same across the 3 processors regardless the voltage. I don't know what causes these discrepancies with the voltages but just because your chip likes higher voltages does not neccesarily make it bad. The lower voltage chips don't run any cooler at the same mhz, they just require a lower voltage. Intel safe limit for vcore is 1.55v so I would say as long as you can get a good clock under that voltage you have a good chip. The lower volt chips do seem to validate higher, probably due to more headroom but as far as priming and stability it's all about the temps, not the voltage!

[roller11]

My 24/7 voltage is 0.953 - 1.129 vcore (voltmeter). This is with EIST hence the range. This allows 4.001 Ghz and never crashes during my most intense desktop apps which for me includes 3D games. My core temps are in the mid fifties during gaming, and my CPU fan (air) is set to just 760 RPM so it is almost inaudible during the most stressful apps.

[Stvwndr219]

have you tried 19x200? I have mine set at that right now and it's running at 1.275v in bios, 1.248 actual. QPI for me is at 1.355 with 12GB of Mushkin 998679(7-8-7-20-1 running at 8-7-7-18-1).

[scottc19]

Have you tried disabling cpuTM function?
Also try 199 and 201 bclk.