i5 Overclock

LEK-89

LEK-89

LEK-89

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Moving on from my RAM thread: http://forums.overclockers.co.uk/showthread.php?t=18295485 I felt that it was time to make a new thread in here.

I've now been looking into & playing with the overclocking on my new rig a bit.

I started off earlier at 4.2Ghz, CPU voltage still at set at auto, turbo boost turned off and booted back into Windows. CPU-Z reported that the CPU was running at 4190Mhz (why is it not at full whack 4200Mhz?) and the CPU voltage was running at 1.320v when idle and 1.22 - 1.30v at full load.

I was then alerted (Thanks to Plec!) that I also needed to turn on C1E in the BIOS (by default it's turned off, this also explained why SpeedStep did not kick in at all after overclocking at first) and after this, idle core voltage was at 1.000v (when SpeedStep automatically kicked in and set the CPU to 1600Mhz) and the CPU voltage was lowered to 1.264 - 1.272v during full load.

Anyway, I've just decided to give 4.4Ghz a go, here are the results. This is with C1E enabled, turbo boost turned off and speedstep turned on:

overclock2.jpg


How does this look to you guys? I'm just after a bit of advice really and if their is anything from the BIOS that I may need to change? How do I go about manually changing the CPU voltage too, if I need to?

Thanks all - Liam
 
Phenomenologica said:
Your clock speed is slightly below what you set because your BCLK is at 99.8 not 100. You can afford to nudge it up if you like. Most people don't advise auto voltage for high overclocks as it can stick uncomfortable levels through the CPU, setting the voltage manually or using an offset is preferred. An offset has the benefit that it will still lower the voltage when idle. I can't advise you on the specifics as I have a Gigabyte board so am not familiar with your BIOS.
Click to expand...

I've just looked in my BIOS again with how to manually adjust the BCLK to 100 and I can't seem to find it. Maybe someone who owns an MSI GDxx motherboard could help me out?

Thanks for pointing out the BCLK to me Phenomenologica :)

Liam
 
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Ok, just had another go just now with the overclocking.

Went back into the BIOS and set everything up for a 4.4Ghz overclock, with speed spectrum disabled and after this I noticed in CPU-Z that at full what it's now dead on 4.4Ghz (Thanks Plec) and I also manually set the core voltage to 1.270v. Rebooted & Windows loaded fine. Ran Prime for just under 10 minutes with these results:

overclock4.jpg


How does this look now? Why is the CPU voltage only 1.256v according to CPU-Z? Shall I keep it set to this voltage or should I lower it a bit more, or shall I just keep it set to auto (when auto, it's always at 1.272v when at full load, and 1.000v when idle)

Thanks - Liam
 
Plec said:
Quick reply just about to go out:

Temps/volts look fine - if you are thinking of sticking at 1.26V then i would consider using auto as you would at least get the advantages of the idle voltage drop as the difference is only 0.012V and temps are very similar (compared to your static voltage clock - although CPUz shows it as a 0.016V diff).

But, personally, i would carry on experimenting to see how low your chip would run at 4.4GHz. But this would be purely for the knowledge as 4.4GHz set at auto, running at ~1.27V is perfectly acceptable - some (unlucky) chips require 1.3V at this speed.
Click to expand...

Thanks Plec :)

I will give it a think over whether to try and go any lower, or whether to stay on auto and run Prime95 overnight tonight and see how things go.

Liam
 
Well - I just got my first BSOD lol!

Decided to try out a bit lower and I set it to 1.260v - booted into Windows fine but then when I started Prime95 on the "in-place large FFT" test, the 3rd test window errors out and stopped and then I stopped the entire test and started again. Soon as I started the second test I got the BSOD - error 124 which means the voltage doesn't it?

Anyway - I'm back at 1.270v now so I will see how I get on.

Liam
 
Well,

Worker #3 failed on Prime5 again within 2 minutes after increasing the voltage back to 1.270v, stopped the test and went back into the BIOS and upped the voltage to 1.280v and rebooted. Worker #3 failed again on Prime95 within 5 minutes so I stopped the test and once again restarted went back into the BIOS and this time set the voltage to 1.300v, idle voltage according to CPU-Z was 1.296v and for the entire time during the test, the voltage stayed at 1.288v - here are the results after running Prime for just over half an hour:

overclock6.jpg


So am I right thinking that 1.288v looks like to be my safe reliable voltage figure for 4.4Ghz? If so - shall I leave it set to 1.300v in the BIOS or is it worth setting it down to something like 1.290v or 1.295v? Looks like I may have one of the "unlucky" chips :(

Thanks all - Liam
 
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As already mentioned - I thought that the lower the voltage, the better? (as long as it's a stable voltage that the CPU can run on)

Liam
 
Indeed 4.4Ghz is the max stable I am after Plec :)

I have just changed the voltage back to auto and I have got Prime95 running as we speak running the small FFT test (is this the best one to do?) and the voltage is sitting at 1.272v again.

So if Prime is sucessful after a few hours, is it absolutely safe for me to leave the overclock settings as they are with the voltage kept at auto?

I started Prime at 8pm, I plan to leave it running until 11pm at least. I will post if the test is sucessful/fail.

Many thanks Plec for your help, you have taught me a lot! :) Lastly, you must have one good chip there for 4.4Ghz @ 1.19v! :D

Edit - Doh! I spoke to soon :( Prime has just failed after 10 minutes with Worker no. 3 erroring out! Shall I test it with the voltage set to manual at 1.3v again?

Liam
 
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Typo error there with 3.3Ghz, Plec? :D

I've got Prime running again now on the set 1.3v voltage (CPU-Z still reporting it being at 1.288v at full load) and Prime is currently 12 minutes in, without any problems.

Would my RAM be affecting this at all? As you know from in my previous thread - I had to manually set the RAM voltage to 1.5v for it run safely at 1600Mhz.

If it errors out again soon I will lower it to 4.3Ghz with the voltage set to auto.

Thanks Plec - Liam
 
Plec said:
I wouldn't have thought so - especially as you were runing small ffts - had it been a blend test there may have been an excuse to up the memory voltage by an increment or two. You've already tested extensively for memory stability (previous thread) so, for now, we'll assume it's not a factor for such a modest clock.
Click to expand...

Yeah I thought it was unlikely that the RAM would affect it, as I have been running it set at 1600Mhz 1.5v manually for the past couple of days now on stock CPU speeds without a problem.

Thanks - Liam
 
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Plec said:
It shouldn't with the static 1.3V - but would if you tried the auto voltage at 4.4 again.
Click to expand...

I've just stopped Prime and gone back into the BIOS. Vdroop is indeed set to Auto, the only options are to change it from auto to Low vDroop. Shall I change it to low and do a prime test again with auto CPU voltage?

Liam
 
Damnit :(

Prime has just error'd again on Worker no 3, 40 minutes into the test!

Do you think that it's best to step down to 4.2Ghz at auto voltage and go on from there?

Thanks - Liam
 
Plec said:
That really depends on you and what you want to get out of the chip.

But as you seemed quite happy with 4.4GHz and cool/silence seems key i would be temped to test 4.3GHz at auto voltages.

I know it's only dropping 100MHz but it could make all the difference.

Or you could try pumping 1.31V @ 4.4GHz as CPUz was only registering 1.27V(?) so you have room to maneuver.
Click to expand...

I've dropped down to 4.3Ghz at auto voltages, CPU-Z is reporting at full load the voltage is 1.272v (same as 4.4Ghz on auto strangely?) and sometimes it goes down to 1.264v but bounces back up to 1.272v, I'm running prime again now. When I was on 4.4Ghz with the manual 1.30v CPU voltage, CPU-Z reported at full load the voltage was 1.288v.

Thanks Plec - Liam
 
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Out of interest Plec,

Why did the test for me fail when on 4.4Ghz, even with the voltage set to auto? I don't quite understand - as when the voltage is set to auto, the motherboard decides the best voltage to run at doesn't it? If 4.4Ghz required more volts when set to auto, then why didn't it get bumped up to 1.31v on it's own?

Thanks - Liam
 
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Aahhh ok I get what you mean. If this now goes through Prime95 sucessfully for a few hours or overnight, shall I leave the voltage set to auto on 4.3Ghz for 24/7 use?

Core i5 2500K
MSI P67A-GD53 (latest 1.C BIOS)
8GB HyperX Genesis 1600Mhz
CoolerMaster CM690-II Lite
XFX 650W XXX Edition
BeQuiet Dark Rock Advanced
GTX570
Seagate Barracuda 1TB 7200.12
Sony DVD-RW

Liam
 
From what I remember reading before I purchased the parts, the BeQuiet cooler does not have it's own regulated fan setting - it connects directly to the motherboard and relies on what setting the motherboard gives it. From what I have experienced though, it seems to run at 100% all the time, even when idle. I don't mind though, as it only runs at 1500rpm and it is very, very quiet.

Definately the quietest CPU cooler I have ever used and with the temps I have been getting with OC'ing, I would recommend this cooler again. Indeed it may not be the best cooler for when OC'ing but say for someone else doing non-extreme OC'ing like me, it definately is more than adequate for the job.

Bulldog - the only explanation I could give regarding what you said is that your using a Gigabyte board. Just saying, as I am using an MSI board.

Liam
 
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