i5 2500k 4ghz OC limit?

[fishingcat]

I followed this Bit-Tech guide: http://www.bit-tech.net/hardware/cpus/2011/01/07/how-to-overclock-the-intel-core-i5-2500k/4 for my Gigabyte Z68X-UD3P motherboard. It works fine at 4.0ghz but at 4.5ghz my PC fails to get past the windows 7 boot animation, and raising the CPU VCore to 1.36V didn't help. Is there something I'm doing wrong, or is it just possible that I have a really bad CPU unit?

Specs/Stats:
i5 2500k @ 4.0ghz
Gigabyte Z68x-UD3P
8GB Corsair Vengeance @ 1600mhz
OCZ 750W ZS PSU
Temp don't go above ~60 degrees on Prime95 at 4.0ghz with a Vcore of 1.36v

Voltages:
CPU VCore - 1.3-1.36V
QPI/VTT - 1.12V
System Agent Voltage - 1.135V
DRAM Voltage - 1.65V

I'm totally new to this so I really appreciate any advice you can give.

 

[Kenmitch]

Don't follow that guide. Most of the things they tell you to change are not needed for a 4.5ghz overclock.

I'd suggest reboot into bios and set the optimized defaults. Reboot into bios again and then set up your memory to run at spec. Change the SATA mode or the other things you changed before your windows install then save and exit.

Your chip might not be a great overclocker as YMMV.

I could maybe help you out as the images from the review look decent enough to figure out setting to help you.

LMK when your back to stock and ready to go. Most likely you'll only need to change a few settings and not a whole lotta them like the guide.

 

[fishingcat]

I'm back to optimized defaults with everything stock, what's next? Thanks for the taking the time to help by the way.

 

[Kenmitch]

First boot back into bios and check the advanced voltages page to see if it's all on auto.

While your in the voltages page see what your vcore options are....Auto does it have Normal?

Then look for the Advance Cpu Core features page and let me know what they are set to.

 

[fishingcat]

Absolutely everything is on auto now. Here are some screenshots of the various settings: http://imgur.com/a/iBrVE

 

[Kenmitch]

Did you look in the Advance Cpu core features page? Need to know if most is enabled or what.

 

[chubbyfatazn]

Are you just jumping from 4.0 to 4.5? Without testing anything in between?

 

[Kenmitch]

Are you just jumping from 4.0 to 4.5? Without testing anything in between?

Like everybody else he want 4.5ghz

His chip will do it. But depending on vcore it might not be feasable to him. The only way to know is do some quick checking.

 

[fishingcat]

Here's the Advanced CPU Core features page: http://imgur.com/5fZCu

I did try 4.2ghz but hit instability whilst running Crystal Diskmark.

 

[chubbyfatazn]

Like everybody else he want 4.5ghz

His chip will do it. But depending on vcore it might not be feasable to him. The only way to know is do some quick checking.

I'm not doubting it can do it, but that's why I mentioned it... "depending on vcore it might not be feasible to him."

I assume you were at 1.36v when testing 4.2ghz, fishingcat?

 

[fishingcat]

I believe so, RAM was 1600mhz @ 1.65V too IIRC.

 

[Kenmitch]

Looks like what you want to start at least.

You do have a decent cooler don't you. The jump from 4 to 4.5ghz can generate some heat.

I would only change the following for now.

CPU clock ratio to 45x
Real time ratio change in OS to disabled

Save and reboot back into bios and look at your vcore and see what it is now. If it looks low as 1.35ish or so then try to boot into window.

 

[fishingcat]

I have a Hyper 212+ in a HAF 932, so cooling shouldn't be an issue. I'll try that now.

 

[Kenmitch]

I'm not doubting it can do it, but that's why I mentioned it... "depending on vcore it might not be feasible to him."

I assume you were at 1.36v when testing 4.2ghz, fishingcat?

The voltage settings that the guide showed would cause instability dependant on the chip. The things it showed to change are not needed at such a low overclock.

Some of the voltages they said to set my chip in sig doesn't even need to boot at 5.5ghz. way ovekill.

 

[fishingcat]

When I set the clock ratio to 45x I bootlooped a couple of times before I could get into the BIOS, and when I did everything had set itself back to default.

 

[Kenmitch]

When you change the multiplier to 45x the options expand on the page? Watching a video on youtube for your actual motherboard shows it does. Look for the turbo power limit and change it to something higher like 150 and try again.

If it still bootloops then you might have to change the Internal CPU PLL overvoltage to enabled and try again.

Good luck

 

[chubbyfatazn]

The voltage settings that the guide showed would cause instability dependant on the chip. The things it showed to change are not needed at such a low overclock.

Some of the voltages they said to set my chip in sig doesn't even need to boot at 5.5ghz. way ovekill.

Yeah, my fault for not reading that bit-tech guide... I never read guides when I OC, just get to know the basics. It's always gonna be chip-dependent.

I didn't keep my last Z68 Gigabyte board long enough to check, but do they still do that CTRL+SHIFT+F1 thing to get a whole 'nother menu? FWIW, my boot loop issue was that the board wouldn't recognize two sticks in dual channel mode. One or two sticks running in single channel mode, it was cool. BIOS update didn't help.

Anyway, I'll bow out now. Best of luck OP.

 

[fishingcat]

I enable CPU PLL over voltage and allowed it to up the wattage. It got to the login screen then BSODed and now it won't even boot into BIOS.

 

[Kenmitch]

The internal cpu pll over voltage is most likely required for your chip to boot at 4.5ghz or high. It's chip dependant if it's needed or not. The combo of the two would't kill anything so don't worry.

I take it your not typing on the rig your trying to overclock.

 

[fishingcat]

I'm currently typing from my phone. It seems pretty dead considering that it turns on and off repeatedly and none of the fans spin. I assume that the CPU has gone completely.

 

[Kenmitch]

I doubt it. Unplug the power supply and then hold the power button to discharge the motherboards capacitors then reset the cmos. Then try and boot up.

 

[fishingcat]

Now it boots to BIOS, so I've set it back to stock. Unfortunately Windows gets stuck on the login screen now. But I assume that's a result of the BSOD rather than a hardware issue.

 

[Kenmitch]

Thats good news! I'd hate to be the guy that helped you kill your rig. The guide you followed wasn't the best one I've seen. Some of the voltages they said to change are on the extreme side.

Did you boot into bios and load optimized default settings yet?

Did you try to boot into safe mode? Might help windows clear back up.

I was playing around at 5.5ghz today and must have added another 25 or so bsods to my bsod'd install. Gonna have to reload pretty soon. Must have 100 bsods on this install from playing with overclocks and voltages

 

[Charlie98]

Do you have 1.65v RAM? If not, set your RAM volts to 1.5v. It's my understanding Sandy Bridge doesn't like anything above 1.5v for memory.

Look at my sig, I have my voltage set below 1.35v with a 41x multiplier, BCLK @ 100.3. Don't fool with the BCLK, either... I BSOD'ed anytime I went over 101.0 BCLK.

 

[fishingcat]

Ok, I managed to get back into windows successfully with optimised defaults (although it had set my SATA mode from AHCI to IDE which caused a hiccup). Thanks for being so helpful, it seems my chip really can't do 4.5ghz though.