i5 750 overclock fails

[skdenktas]

Hello everybody,

I need some help to overclock my i5 750. I am using Gigabyte P55-UD5 mobo, 4x2gb Kingston HyperX Blu 1600 Mhz Rams and OCZ Fatality 750 watt PSU.

One month ago, I installed a Hyper Evo 212 cooler with using Xigmatech G3606 thermal paste. Then I overclock my cpu to 3.6 Ghz (200x18) without voltage tweak. I tested with Intel Burn Test at maximum. My temps were 75 C max. I used it like that for a month without any problem.

I have been in a business trip for 3 days, my wife told me that she did not open my pc after hibernation couple of times, then it was opened.

When I came, I noticed that my bios lowered the settings to 2.4 Ghz. Then I tried to overclock again with the same specs (200x18), but I could not manage it, everytime it failed at the start-up. After few attempts, I managed to overclock it to 3.6 Ghz with using 180x20. What could be the reason of these failures?

By the way, I could not manage to change any voltage settings. Whenever I did that, it failed at the start-up. I only closed turbo, all the other things were at Auto or default.

I also tried to overclock it to 3.8 Ghz (190x20), my pc opened without any problem, but Intel Burn test failed at maximum in the third cycle, even if my temps were 76 C max.

Do you have any suggestions to overclock my pc to at least 3.6 or 3.8? My problems could be related to LLC, QPI clock or failure of a ram (Because my rams are now working on 1440 Mhz (180x8), before that I was using them on 1600 Mhz (200x8)?

I am new at CPU overclock and English is not my mother language. I'd be glad if you explain reasons and suggestions more clearly.

Thank you all.

 

[Denithor]

Welcome to the forums!

The first thing I would check is that the PC is still fully functional at stock settings. Does it pass IBT with everything at default in BIOS? If not, you have a hardware problem, I would start checking with RAM and PSU first.

If IBT stable at stock, then begin overclocking again, but this time go up slower. Start around 3GHz (150x20) instead of jumping up to 3.6GHz immediately. Check IBT stability at each point to confirm you're okay before moving up further.

 

[Burpo]

I managed to overclock it to 3.6 Ghz with using 180x20. What could be the reason of these failures?

If it's back up & running at 3.6 stable, you should be happy with that..

But here's overclock videos w/your cpu & similar board..
https://www.youtube.com/watch?v=dLW9adkHNbY
https://www.youtube.com/watch?v=Iy8D7bbxHXg

 

[Geforce man]

I would imagine, that similar to my old i5 750 setup, and many others, that your bios settings were completely reset. This may be caused by a dead motherboard battery or something, or the overclock failed.

I would imagine that the memory settings were set back to default, which used some form of multiplier to go from the standard 133 or 166 FSB speeds to get to 200Mhz. So when you are trying to go to 200Mhz speed, you are running the memory out of spec. Try to see if there is a memory multiplier option of 1:1 in your bios, and hopefully you can return to your 200Mhz FSB speed.

 

[sm625]

That's pretty much what happened to my i5-750. It was stable at 3.6 for months. Then one day the bios was reset and I could no longer do 3.6. So I did 3.4. Same story with 3.4 after a few months so I went with 3.2. After two years I was down to 3.0. Six months later even that failed. And then I went to a G3258 at 4.5 lol.

 

[skdenktas]

I would imagine, that similar to my old i5 750 setup, and many others, that your bios settings were completely reset. This may be caused by a dead motherboard battery or something, or the overclock failed.

I would imagine that the memory settings were set back to default, which used some form of multiplier to go from the standard 133 or 166 FSB speeds to get to 200Mhz. So when you are trying to go to 200Mhz speed, you are running the memory out of spec. Try to see if there is a memory multiplier option of 1:1 in your bios, and hopefully you can return to your 200Mhz FSB speed.

The multiplier is 8. In my old overclock I was using like 200x8=1600 Mhz, but now I changed my setting for stable overclock after failure to 180x8=1440 Mhz. I could manage to use the old settings again. I even manage to open my computer at 190x8=1520 Mhz, but it failed at IBT maximum on 3. I think that it could pass IBT at very high. Maybe I could use these settings, I don't think CPU will not be working at that maximum load with internet, gaming or watching HD videos. I read that some people using their pc with an overclock which has failed in IBT maximum. Do you think that these tests are little extreme?

 

[skdenktas]

That's pretty much what happened to my i5-750. It was stable at 3.6 for months. Then one day the bios was reset and I could no longer do 3.6. So I did 3.4. Same story with 3.4 after a few months so I went with 3.2. After two years I was down to 3.0. Six months later even that failed. And then I went to a G3258 at 4.5 lol.

Do you know what is the reason? There is a lot of people using their i5 750 at 3.6 - 4.0 overclock more than a year.

 

[Geforce man]

I was not referring to your processor multiplier, but your memory. I do recall gigabyte called it something weird, but you want your FSB / Memory to be at the same Mhz, or a 1:1 ratio, if possible. I had my i5 750 @ 4.2Ghz for 2 years, and it ran just fine. Granted it was water-cooled and I seem to have had a golden sample, but it was a great chip for its time.

 

[beginner99]

Do you know what is the reason? There is a lot of people using their i5 750 at 3.6 - 4.0 overclock more than a year.

My i7-870 (basically same processor as a i5-750) been running at 3.6 (+ turbo) for about 5 years with now issue and no voltage raise. CPU lottery, soem get lucky others not so much.

 

[skdenktas]

I checked your suggestions yesterday. As I told you, I could overclock my cpu with 180x20, but my rams were 1440 Mhz in this way.

I bought 2x2 gb Kingston HyperX Genesis, when I first got my PC in 2010. Last year I bought 2x2 gb Kingston HyperX Blu.

I noticed that Genesis rams are running at 1333 Mhz, Blu ones at 1600 Mhz, but Genesis rams also can run at 1600 Mhz. I guess that this could be the reason not to overclock with 200x18, but I am not sure. Why my old rams could not get higher Mhz now, does anyone have an idea?

 

[skdenktas]

I solved the problem. After I updated the BIOS, I could manage to overclock 200x18 again. I tweaked only the core voltage to 1,35 and dram voltage to 1,65.

Then I tested with Intel Burn Test a maximum, everything is ok for now, max temp was 74 C.

Thank you all guys for your comments.