A good (detailed) guide to overclocking i7s?

JonJ678

JonJ678

JonJ678

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I don't seem to be doing very well with Google here. My system is at least slightly stable, intel burn test on XP is never the most thorough approach but at least it passes. However I'm aware that when it isn't stable, I'm not going to know what to do.

What I have so far,
Ram is running within spec. A bit underclocked, but at the right voltage.
Vcore is at 1.3V bios, 1.2V load cpuz
QPI voltage at 1.295V
bsck at 200

Uncore is at x16 since the ram is at x8. I believe this is appropriate, the uncore has to be below 4ghz or so?
QPI frequency is at the minimum I can set
Load line calibration is off, and I'm not really open to argument on this one
Turbo mode is off, at least until I can work out how to turn off turbo throttling in the bios

I've set every other voltage I can to its stock setting, just because this is what I used to do on the last generation.


Load temps are at 60 so will be ignored until further notice. When it fails to be stable I intend to throw more voltage at qpi, staying below 1.35, and at vcore, staying below 1.4. This is fairly amateurish and I'd like a more refined approach really, so where should I be looking?

Hoping for a link, but if some kind soul cares to educate me in person I'll hardly object. Cheers
 
Ok, no LLC so we have to compensate for .9v vdroop on the ud5.

from the top of the bios.....

CPU CLOCK RATIO: x20
Advanced Cpu Features: all enabled with the exception of C3/c5/c7 state support.
QPI CLOCK RATIO: x36
UNCORE CLOCK: x16

Advanced Clock Control:

BCLK: 191mhz
PCI Express: 101mhz
CIA: DISABLED.

CPU CLOCK DRIVE: 800mV
PCI Ex CLOCK DRIVE: 900mV

Performance Enhance: OFF
XMP: OFF
System Memory Multi: x8

Memory settings at your disgression, I dont know what memory you've got.

VOLTAGES:

VCORE: 1.287v
QPI: 1.215v
IOH: 1.1v
DRAM 1.5v - 1.66v

test that, if unstable increase the QPI first up until 1.335v, then the vcore until stable. then reduce the QPI until unstable and add 2 steps, do the same with vcore. Also the IOH can be increased, 1.14v seems to be popular.

A lot depends on the CPU itself, none are the same.The 191 bclk is easier to hit 4Ghz (with speedstep on), when you get it stable then you can experiment with different bclk. Throttling will only occur when the tjmax is reached 100c, and you dont want to be anywhere near there to begin with.

I hope this helps.
 
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Hi Jon,

There is a stack of stuff around the net about clocking these chips, here are a few links that might be of interest to you.

http://www.xbitlabs.com/articles/cpu/display/core-i7-920-overclocking.html

These next two are probably more geared towards EVGA mobos, but still worth a read imo.

http://www.evga.com/forums/tm.asp?m=100494809&mpage=1&key

http://www.evga.com/forums/tm.asp?m=716108&mpage=1&key

This one is more for C0 stepping processors, but again still worth having a read as well.

http://www.tweaktown.com/news/10827/gigabyte_shows_how_to_overclock_i7_920_cpu_to_4ghz/index.html

Other than those guides, just read through peoples posts on the forums you frequent to learn more about overclocking these chips..

Also, I find using LinX is much better than IBT, in that it doesn't have the 8 thread bug that IBT does, so it fully loads the processor with 8 threads unlike IBT where you have to use 16 threads to fully load your chip..

I know you have said you kinda want to avoid using turbo mode, but I have found that it takes much less Vcore to get 191 Bclk stable than it does 200.. it took me ages to get 200+ Bclk stable, however 191 was a walk in the park..

And I have never witnessed any throttling of any sort when using the 21x multi, I think temps have to be in the mid 90's before throttling occurs..
Good luck mate.
 
@Gaidin It does a bit, though I was hoping for an explanation for some of the options rather than a list of bios options. I believe I've turned off most of the advanced features, I'm not interested in energy saving at present and don't like the idea of turbo.

I have 700mV for both clock drive, Google thinks I should 'load optimized defaults' to change hidden settings to better match my system at which point I think they'll match yours. I'm not very sure about this at all, my previous motherboards 'optimizing' efforts have not been good. Or have you set these manually?

I think your post summarises as increase QPI and vcore as required, which is basically all I'm doing at the moment. I'll look into IOH, as I don't know what that is.

@DavyBoy, I shall read these now. Thank you. I think the bug is always failing when testing with 8 threads, and I'm passing so don't feel too worried. It's a fairly old cli interface though and may not be the version people had issues with. Running prime blend now while looking for leaks (bad form I know), and nothing's leaking and no failed tests an hour in. Heading to sleep soon so may as well run it overnight, temperatures will get better when it's bled anyway.

Are you sure it's not throttling?

Thanks guys
 
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Yup Jon, loading optimized defaults set CPU clock drive to the values Gaidin suggested.. or at least it does on my system..

::edit::

I posted some links that might be of interest to you..
 
DavyBoy said:
Yup Jon, loading optimized defaults set CPU clock drive to the values Gaidin suggested.. or at least it does on my system..

::edit::

I posted some links that might be of interest to you..
Click to expand...

I didnt actually know that, I spent ages mucking about with it and reading posts. :rolleyes:
 
IOH Core is Northbridge voltage.. it can help with stability I have found..

Also, when I was first trying to get my system stable, I would always first set my BIOS to optimized defaults, then save and exit, then re-enter and make my changes for my overclock..

I was advised by someone on another forum to do this..

::edit::

Yeah Gaidin, optimized defaults sets those values for you..
 
look at my sig mate, click the CPUZ banner.. 220 on this chip I am using atm, only SuperPI stable though, far from being Prime or LinX stable. haven't tried any higher tbh, but these mobos have a 222 bclk wall unless you hardmod them..

Best place to look for high Bclk is over on XS.
 
IOH is northbridge voltage like DavyBoy said, dont leave it on auto because the UD5 has a habit of putting some crazy volts through it otherwise. I found its better to set it manually even if its the default 1.1v.

As long as you keep under the 100c TJ max by a 15c margin you wont get any throttling. What cooler are you using?, any of the high-end aircoolers shouldnt get anywhere near core temps that would engage throttling.
 
Good links on the evga forums, thank you for those. Some parts of diagnosing crashes strike me as slightly optimistic, but good information there.

Its not just temperatures, it throttles based on current draw as well. Turbo looks like being bribed into using speed step to me, and I distrust it as a result. XS think there's an option which leaves you with the +1 multi but turns off all the throttling mess, but I'm not sure which it is.

Was that on air Dave? Some serious voltage being pushed there.

Optimized defaults is probably worth a punt. I'm trusting Gigabyte with a lot of other settings anyway. I might ask their forums what this actually does, but their support isn't exactly swift.

The risk with XS is that it starts to seem reasonable to take a soldering iron to your motherboard. What are you at now Samsung? 200 doesn't seem to be giving me any trouble at all, might cut prime short to see if it'll boot at anything higher
 
DavyBoy said:
look at my sig mate, click the CPUZ banner.. 220 on this chip I am using atm, only SuperPI stable though, far from being Prime or LinX stable. haven't tried any higher tbh, but these mobos have a 222 bclk wall unless you hardmod them..

Best place to look for high Bclk is over on XS.
Click to expand...

Im not looking for more than 220 BLCK but seem to be hitting a wall at 207 BLCK. Would like 215 for 4.5Ghz. I freeze on post screen so makes me think im missing something.
 
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Could be your chip mate, my other i920 won't boot into Windows with more than 217 Bclk, and I have tried some pretty crazy uncore and Vcore!!!!

It gets to the Win7 loading screen, and just as the logo is about to pop up it freezes..
 
Which batch is your processor?

::edit::

LoL, I just noticed you edited the post above with a link to unclewebb's i7 turbo app, and I have went and posted the same link in my previous post...

This thread is getting confusing guys, I am going to bed before my brain shuts down from exhaustion!!!

Good luck Jon.

Laterzzzzzzzzzzz peeps!
asleep-045.gif
 
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Oddly Samsung I freeze on the post screen at 210. In different places each time, but neither more vcore nor more qpi helped. It might be board related, but that doesn't feel right somehow. I'll give you a shout if I make progress on that one.

Good news Dave, is there anything you set specifically to disable it?

My temperatures seem to be 60 under load at 200x20, 1.3V vcore. My loop is an absolute mess but seems to be functioning despite my concern that it wouldn't be able to cope.
 
Gaidin109 said:
Ok, no LLC so we have to compensate for .9v vdroop on the ud5.

from the top of the bios.....

CPU CLOCK RATIO: x20
Advanced Cpu Features: all enabled with the exception of C3/c5/c7 state support.
QPI CLOCK RATIO: x36
UNCORE CLOCK: x16

Advanced Clock Control:

BCLK: 191mhz
PCI Express: 101mhz
CIA: DISABLED.

CPU CLOCK DRIVE: 800mV
PCI Ex CLOCK DRIVE: 900mV

Performance Enhance: OFF
XMP: OFF
System Memory Multi: x8

Memory settings at your disgression, I dont know what memory you've got.

VOLTAGES:

VCORE: 1.287v
QPI: 1.215v
IOH: 1.1v
DRAM 1.5v - 1.66v

test that, if unstable increase the QPI first up until 1.335v, then the vcore until stable. then reduce the QPI until unstable and add 2 steps, do the same with vcore. Also the IOH can be increased, 1.14v seems to be popular.

A lot depends on the CPU itself, none are the same.The 191 bclk is easier to hit 4Ghz (with speedstep on), when you get it stable then you can experiment with different bclk. Throttling will only occur when the tjmax is reached 100c, and you dont want to be anywhere near there to begin with.

I hope this helps.
Click to expand...

I had done the same setting what you had, I was surprise I get very low temperature and been full load on prime95 for an hour with stable with load line calibration disabled and lower my IOH down to 1.14v. Many thanks for your best overclock advice. You had a great skill of overclock pc.
 
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