Intel i5-760 overclock help

[nrage]

System specs:

Asus P7P55D-E (Intel P55)

Intel Core i5 760 2.80GHz (Lynnfield)

GSKill (2x4GB) DDR3 RipJaws X PC3-12800 1600MHz (Model Number: F3-12800CL9D-8GBXL)

Noctua NH-D14

When I first got the system I noticed the idle temps with stock cooler were 50-60 degrees, and under load would reach 80-90 which was just ridiculous. So, I decided to get a cooler, and then I figured if I was going to buy a cooler why not buy a good one and try some overclocking. So, I grabbed a Noctua NH-D14 followed TinyTom's overclocking instructions in his review of the i5-760, eg.

1. Set core voltage to 1.25v

2. Enabled load line calibration

3. IMC volts - I left these untouched as my RAM is at stock.

4. Set my RAM to stock settings: Voltage (1.5v), Timings (9-9-9-24-2N) .. I left the many other RAM timing components on auto.

5. IOH core .. my bios does not have a IOH core setting, it does have PCH which I think is the replacement on Intel P55?

6. C1E disabled, SpeedStep disabled

7. BCLK to 200Mhz, Multiplier to 20

I started with a lower multiplier and worked my way up to 20, just to be safe

At 200 x 15 (3Ghz) it was stable in Prime95 for 20 mins and temps didn't exceed 60 degrees

However at 200 x 20 (4Ghz .. my target) in Prime95 for 5-15 mins one core/thread failed with a hardware failure. What I want to know is where/what to tweak to find stability. I am a complete noob at overclocking and I don't just want to mess with everything in the hope of figuring it out, I'd rather understand what/why I am changing things and only increase what needs to be increased to get it stable.

I tried bumping the PCH voltage up 1 then 2 increments, assuming this was like bumping the IOH core, as included in the original instructions .. this made no difference.

So, other options?

1. I plan to reset that to auto and bump the IMC volts up a notch or two, just in case it's a RAM related fault.

2. Another option is to up the RAM voltage directly, but it is running at stock speeds so I assumed this is unnecessary.

3. I did read somewhere that the P7P55D-E may not have high enough quality components to handle a 200 BCLK, so another option is to bring that down to 190 with x21 multiplier or similar.

On a related note, has anyone overclocked GSKill RAM like mine on P55.. how do I go about doing it, and is it safe with only stock heatsinks and any overflow from the NH-D14?

 

[ruthless_villain]

bump up the cpu voltage dude, most commen problem, i got 4.2ghz on a i5 760 using that board and ram doesnt get hot unless you do some lethal overclocking

 

[Grizzly]

Set it to 1.4V (max safe volts on that chip), then when you've got an overclock you're happy with, drop the voltage until it's as low as it can get without being unstable.

 

[nrage]

bump up the cpu voltage dude, most commen problem, i got 4.2ghz on a i5 760 using that board and ram doesnt get hot unless you do some lethal overclocking

So, with this board I shouldn't need any IMC or PCH (aka IOH) voltage increases to get this stable at 4Ghz?

Do you remember what core voltage you were using?

Set it to 1.4V (max safe volts on that chip), then when you've got an overclock you're happy with, drop the voltage until it's as low as it can get without being unstable.

I am happy with the 4Ghz I've got so far, I just want to find the stable voltages. I'll drop the PCH voltage back to auto and bump the core voltage instead. I could start at 1.4 and come down.. might be a good test of the cooler if nothing else.

Thanks guys!

 

[nrage]

Ok.. So I just bumped the core voltage up a notch to 1.256v and now Prime95 runs without errors for 10-15 mins then itself crashes... does this mean the system is still unstable? Or do I have a problem with Prime95 itself... seems unlikely. I guess I can bump the volts up one more notch..

 

[nrage]

Interesting .. after reading this:

http://www.playtool.com/pages/prime95/prime95.html

I tried the Small FFTs torture test, which apparently focuses on the CPU and does not involve the IMC or RAM and it was stable for a good 20-30 mins. But, large or blend and it fails in 10mins or less.

Is the answer still to bump the core voltage? Or do you think bumping IMC will help? .. or the RAM voltage itself?

 

[ruthless_villain]

this wont be much help, but this is why the i5 2500k merks

 

[JezEngland]

Hi. My i5 750 is @ 3980.85MHz, 209.52x19, DRAM 1672MHz + 1.65 Volts, CPU Voltage 1.3125, IMC Voltage 1.3515, PPL Voltage 1.802, PCH Voltage 1.06, on an ASUS Maximus 3 Formula. You might need more Voltage for your board.

Your 760 should want similar though the motherboard might not like or survive 209MHz Base clock - BCLK

I recall having 4Ghz with a lower BCLK and the IMC Voltage was alot lower. I use AUTO for most stuff and it's OK

 

[nrage]

Hi. My i5 750 is @ 3980.85MHz, 209.52x19, DRAM 1672MHz + 1.65 Volts, CPU Voltage 1.3125, IMC Voltage 1.3515, PPL Voltage 1.802, PCH Voltage 1.06, on an ASUS Maximus 3 Formula. You might need more Voltage for your board.

Your 760 should want similar though the motherboard might not like or survive 209MHz Base clock - BCLK

I recall having 4Ghz with a lower BCLK and the IMC Voltage was alot lower. I use AUTO for most stuff and it's OK

Thanks for the numbers. What I have done is gone back to my initial settings, except I dropped the multiplier one notch to 19x, giving me 3.8Ghz instead of 4 (@1.25V core, auto on the rest). This now appears to be stable (prime95 for 1-2 hours) so I am happy with that, I'm not trying to push it to the limit, and I think I'll get more by adding a ram overclock now.

So, does anyone have advice on how/what to attempt to overclock my GSkill 2x4Gb sticks to? For example, do I just bump the Mhz, and voltage? .. what are reasonable expectations, taking into account the cpu overclock and motherboard limitations?

Current settings are base: (link to GSkill site)

Timings: 9-9-9-24-2N

Speed: 1600Mhz

Voltage: 1.5v

Can I just bump the speed to 1800, or 2000.. what kind of voltage increase should I try with that?

Do I have to loosen the timings? I expect so, so do I start really loose and tighten each in turn testing stability each time?

What is the best way to test the overclock? Memtest86+ or Prime or ...

 

[Ghosthud1]

Sorry about the size! (thats what he said)

there the settings i have on my 24/7 4ghz OC on a 4 phase motherboard.

msi h55-ed55, You have a D14 so dont be afraid to wack the volts up to get it stable.

Your ram can go upto around 1.65-7 volts i think. maybe a little more!