Problems with i5 2500k slightly OC (auto to 4000Mhz)

[Hrokthar]

Hi guys,
I have started to have some problems with my PC (components described bellow) recently. Sometimes restarted during playing game after I switched to automatic OC done by mainboard. So I started reading a bit about OC and did some adjustments:

Let MB to do OC automatically using Asus EZ setup. Then reduced Turbo from 4200Mhz to 4000 only. Manually changed RAM to 1666 from 1333 done by MB and also set voltage to 1.65V on RAM. That's actually all I have done and everything should be ok. BUT it is not.

OCCT fails - everything seems ok, temperature around 60 and then suddenly temperature goes up to 120 for like 1 second and CPU Voltage to 0 and OCCT ends test.
Prime95 restarted computer (dunno when exactly did it over night)
Memtest 86+ - is ok running like 4 hours with no error

Please do you have any ideas what could be the problem? Should I let MB to switch RAM to 1333 and lower voltage? Or should I try so set Voltage of CPU lower then MB does? (100.33x40 is set to 1.256 in Turbo by MB). Or just give up OC what would be shame because of capability...

My HW:

Mains parts:
MB ASUS P8Z68-V, Intel Z68 – last firmware
CPU Intel Core i5 2500K
RAM Kingston HyperX Genesis Grey 4x4GB DDR3 1600 MHz CL9
SEASONIC M12II-620 - 620W (80PLUS Bronze)
Graphic Card Gigabyte GeForce GTX 660 Ti OC, Windforce 3X, 3072 MB DDR5
Case - AeroCool ExtremEngine 3T BBA (Aluminium door)

Cooling:
CPU - Noctua NH-U12P + Noctua NM-I3 Secufirm2
Paste - Noctua NT-H1
Case 1 - Noctua NF-R8 PWM
Case 2 - Noctua NF-R8-1800

SDD+HDD:
SSD 335 Series 240GB, SATA 6Gb/s – updated firmware
1x SEAGATE Barracuda Green 2000GB
1x Western Digital WD30EFRX 3000GB

To show you what is going on please find attached results from the beginninng of Prime95:

[de.das.dude]

automatic OCs are worthless for normal usage. for daily use you need to OC the system yourself. auto matic OCs are hardly ever stable.

OC the system yourself. but i would advice you to get some real experience in OCing before you try. try it on some cheap alternative computer first.


i have even seen some automatic OCs that destroy the CPU. for eg saw this FX4100 OC to 5GHz at over 2Volts!

[Naito]

Auto settings tend to throw voltages to high defaults to support clocks, even if the increase, or and increase of such as size, is needed or not. May be a cause of instability. Do as DDD suggested; get a cheap rig to learn manually tweaking of OC, if you are new to this.

[Naito]

Proceed at your own risk: Here is the datasheet for the 2nd Gen Core i series. See Section 7.10 for DC specifications regarding voltage range, limits, etc. Make sure no voltages go beyond these limits, auto or otherwise.

[erixx]

Leave everyting in the Bios regard overclocking and CPU settings on AUTO.

Set your RAM as you alread have to 1600 and 1,65v

Your BCK to 100

Multiplier ("for Turbo") : 40

Volt should be in the 1,2 range. Try auto volt. Check after restarting, reenter BIOS, it tells you in the Voltage Monitor section. If too high (above 1,35v) , lower it. Maybe you can even use the stock voltage as 4000 is just slightly above stock.

Asus tells you with colors if the numbers are too high in the BIOS. Stay with yellow or blue numbers, never red ones.

Using an old computer (with ANOTHER processor family) to learn this, I think is overkill, unless you want to graduate in Overclocking

[Crap Daddy]

Originally Posted by erixx

Leave everyting in the Bios regard overclocking and CPU settings on AUTO.

Set your RAM as you alread have to 1600 and 1,65v

Your BCK to 100

Multiplier ("for Turbo") : 40

Volt should be in the 1,2 range. Try auto volt. Check after restarting, reenter BIOS, it tells you in the Voltage Monitor section. If too high (above 1,35v) , lower it. Maybe you can even use the stock voltage as 4000 is just slightly above stock.

Asus tells you with colors if the numbers are too high in the BIOS. Stay with yellow or blue numbers, never red ones.

Using an old computer (with ANOTHER processor family) to learn this, I think is overkill, unless you want to graduate in Overclocking

Pretty much this. Definitely auto voltage should be fine for even higher than 4 GHz. I would add to check if the heatsink is mounted properly.

[Hrokthar]

Guys,
thanks for your advices. After playing a while with volts it seems to be stable now (running Prime95 over 3 hours with degrees under 60) with all saving utilities (TPU, etc.) enabled. Was trying to set - offset to get to around 1.2 V and now is it between 1.185-1.2 during test. Wanted to avoid setting it manually to 1.2 as in iddle it woudn't go lower..

Btw. also tried 4.5 GHz with some guidelines on youtube but wasn't lucky with temperatures. Went over 80 degrees in like 10 minutes . Seems like cooling is not enough for some reason...

If I would like to go to 4.2 GHz it is still ok to have all on auto right? Just to add some Volts?

[1ceTr0n]

This is why I love ASUS ROG mobos, a few simple setting changes and my i5 2500k runs at 4.6ghz on stock voltage.

[deejeta]

Dont use auto oc anything. Will always overvolt.
There are plenty of resources both here, other forums and google about overclocking.
Dont just plug in someone elses bios values as each chip is different depending on how you went in the silicon lottery.
The 2500k is an amazing piece of kit. You may be lucky in getting one that can hit 5ghz on reasonable volts or you may have one that can only reach 4.5 without crazy vcore.
Just watch your volts and temps.
Good luck.

[erixx]

I have my offset set at -0.02 and my voltages go from 0.9 v for 1600Mhz (idle) up to 1.32 v at full load (benching) at 4400 Mhz. Temps use to stabilize during testings or gaming before reaching 60ºC. I am using a Noctua and well aired case.

For Asus boards: also check your EPU settings in the EPU panel in AISuite, there are a few options. Specially I like the one that turns your case fans off when idling.

[Hrokthar]

Having strange situation here. Prime95 is running 3.5 hours with no error. OCCT linpack has error after 31 minutes just when CPU goes during test to idle for second time. No specific error just "error" message. The most strange is that voltage is higher in idle then in load. But as I see CPU-Z when computer is normally in idle there is usually like 0.9V.. Dunno maybe will just ignore OCCT results (seems strange as you can see on picture bellow)? Or maybe switch off some saving utilities?



@erixx - I have in EPU just option to take medium, high etc.. Nothing like switch off fan during idle.. And also have problem as have 2 small 80mm Noctua in case (case 1 and 2) but one is new version (with PWM) and second one old. So the one with new revision works ok on like 1500rps but second one goes for 2500rps. Have to change that older one as it's so noisy even in idle

[de.das.dude]

always switch off power saving abilities when you OC. they tend to make the system unstable 90% of the time

[brandonwh64]

Originally Posted by de.das.dude

always switch off power saving abilities when you OC. they tend to make the system unstable 90% of the time

This maybe true on AMD and older intel systems but newer SB and IB actually benefit from having the powersaving features on. Ask cadaveca about this. He has review countless SB/IB motherboards and CPU's and he even told me when he was helping me OC SB for the first time was to leave these features on.

[erixx]

I use my computer all day and often let it on at night, so I early understood that I can't live without powersaving (heat+money+degrading/stress on parts), so since years I always overclock leaving powersaving ON. Per-fect-ly pos-si-ble!
Only exception would be if you turn your PC on only for an hour or so a day. Or AMD, who knows. :P

[RCoon]

Auto is just plain silly, you should set it as a permanent OC. manually set multiplier, bus speed, ram and voltage. Auto will overvolt to silly point. Set your load line calibration to high or very high, stick it at 4ghz, and manually set your voltage on the cpu to stock voltage. Test and see how that goes.

[Aquinus]

You should see much higher clocks at that voltage. As RCoon said, I would manually set the voltage. I did that on my 3820 and I was about to get 4Ghz at .08-.1v under stock. I suspect that your 2500k may do the same thing. Just work the voltage down until it doesn't go lower.


This screenshot was while I was running LINPACK.

[brandonwh64]

Stock settings should render 4Ghz with only a touch of the multi to X40

[RCoon]

Originally Posted by brandonwh64

Stock settings should render 4Ghz with only a touch of the multi to X40

Pretty much this.
When i get a new processor, the first thing i do is a fractional overclock and reduce the voltage on the core. You'd be suprised how often you can reduce your thermals because the processor runs stable at lower voltage.

[brandonwh64]

My ASRock Z68 Pro3-M (lower end board but still great) rendered 4.2ghz on all stock settings except the multi changed to 42x so that is were I would start if you want just a slight OC.

[Crap Daddy]

Originally Posted by brandonwh64

My ASRock Z68 Pro3-M (lower end board but still great) rendered 4.2ghz on all stock settings except the multi changed to 42x so that is were I would start if you want just a slight OC.

Actually that's what I also settle for. My board can do up to 44x just by changing the multi but it can't sustain under stress without changing the power limit settings and drops to 42. So for my needs it's more than enough. It's true that the voltage is a bit higher than if I'd start tweaking it (1.280) but I had no stability problems ever. All power saving modes enabled.

[Hrokthar]

I am just wondering that if I will manually set Voltage to 1.2 instead of adding just +/- to offset, how will change consumption and heating. Frequency will drop in idle to 1600 but if Voltage is same, there is the same heating and same consumption as during test? Or am I wrong?

I also sometimes leave computer over night running for downloading and use it also for playing movies sometimes. So it would be more costy to leave it running at 1.2V all the time Just don't know how much..

[brandonwh64]

Originally Posted by Hrokthar

I am just wondering that if I will manually set Voltage to 1.2 instead of adding just +/- to offset, how will change consumption and heating. Frequency will drop in idle to 1600 but if Voltage is same, there is the same heating and same consumption as during test? Or am I wrong?

I also sometimes leave computer over night running for downloading and use it also for playing movies sometimes. So it would be more costy to leave it running at 1.2V all the time Just don't know how much..

If you set voltages manaul then yes it will stay at what you set and not go down. My advice would be to clear the CMOS then do as I mentioned and ONLY change the multi to 40x then test for stability and temps. If it works great then move multi to 42x and retest.

[Hrokthar]

Originally Posted by brandonwh64

If you set voltages manaul then yes it will stay at what you set and not go down. My advice would be to clear the CMOS then do as I mentioned and ONLY change the multi to 40x then test for stability and temps. If it works great then move multi to 42x and retest.

I did in past but voltage went up to like 1.35 for 4Ghz. So not so cool That's why I started lowering it.. And it was unstable with auto like this..

[brandonwh64]

How do you know if the software you are using is showing the proper voltages cause with all the power saving features, the voltages flux all over the place.

[Hrokthar]

Originally Posted by brandonwh64

How do you know if the software you are using is showing the proper voltages cause with all the power saving features, the voltages flux all over the place.

This is when I did reset of bios, changed ram to 1600 and their voltage to 1.65. And also changed freq of CPU to 3.8Ghz only.. Was not stable..


And this figure during that test is bit strange because falling but don't know if this caused problem or what..