Need Help Overclocking i5 750

[moe112]

Hey guys, I recently put together my first pc and I'm now intrested in overclocking it. But I have a few problems I'm completely new to this so I need detailed instructions. I'm after a decent overclock nothing over the top say 3.2 - 3.6GHz, this is my setup.

Intel Core i5 750
Asus P7P55D-E PRO
Kingston 1333MHz 4GB DDR3
Asus Radeon HD 5770
Antec 900
Zalman CNPS10X Performa (havn't ordered it yet, can you recommend something better under $60AUD)

Here is a pic of Core temp & CPU Z, why is my core speed at 1203.7MHz? I thought I purchased a i5 750 2.67GHz. Any help would be greatly appreciated.

 

[iqvl]

OCing guide for noobs:
http://www.tomshardware.com/forum/256144-29-1156-core-overclocking-guide

BTW, the screenshot is too small to see.

 

[moe112]

Sorry about that, just click on the picture and it will open a new window with a bigger version.

 

[iqvl]

This bigger version is kind of blur, but at least it is readable now.

BTW, the guide I linked to and MB's manual should be all you need to achieve 3.6GHz.

OR

Try the setting listed in that guide: (you should achieve a stable OC at 3.6GHz "near" these voltages)
3.6GHz: (24hrs Small FFTs test, 30hrs-2mins Large FFTs test and 14hrs-12mins Memtest86+ stable!)
Load-Line Calibration: Enabled (or Level2 for Gigabyte GA-P55A-UD5)
Vcore= 1.20V (CPU-Z idle)
QPI/Vtt/IMC= 1.14V
PCH= 1.10V
PLL= 1.80V
RAM= Specified voltage for your RAM

 

[moe112]

Sweet as, I'll give it a go soon as the heatsink gets here. Thanks for the help mate.

 

[iqvl]

Good luck!

 

[wolfram23]

Reading guides is a great way to learn. So is actually doing and testing.

If you haven't checked, just fyi the maximum Intel specs are 1.55V Vcore, 1.21V Vtt, and 1.65V DRAM. You should not exceed these - Vcore has lots of head room but the Vtt is limiting; I fried a mobo at 1.28V Vtt.

My current i5 750 OC I'm very happy with as it's fast and with turbo boost on. You can probably get lower stable voltages without turbo, but it was my goal to keep it on. The voltages are just guidlines, you can't just copy and paste... always fine tune to the lowest stable you can get.

Currently:
Vcore: 1.30635V
Vtt: 1.20625V
All other voltages are at AUTO
C1E, EIST, C States (C3), Turbo are all on
175 base clock

(Note: on my fried MSI P55GD65 mobo, I had it stable with the same bclk/speeds/settings but Vcore 1.288V and Vtt 1.18V IIRC so you can see how it's important to try fine tuning your own voltages)

You can only get turbo on with 20x (or 21, technically) multiplier. If you don't need turbo then you can get away with a higher base clock in order to match your RAM speed (such as a 200bclk with only a 16 or 17 multiplier, and 8x RAM for 1600mhz). When OCing your CPU you should generally underclock your RAM so it won't give issues and once you get to the CPU OC you want, then get the RAM set properly. I'm running my 1600mhz RAM at 1400mhz with lower timings so it's basically the same speed overall. Just keep in mind that your possible RAM speeds depend entirely on the base clock.

Testing wise, Prime95 small FFT overnight is great for a final stability check. Blend tests are good for checking RAM stability. For faster testing while fine tuning I prefer Intel Burn Test (high stress) 10 or 15 passes. If you get any errors, you need more voltage. Generally I like to only increase Vcore OR Vtt not both together otherwise you'll never know which really needed the boost. If raising, say, Vcore by up to .1 V (in, say, 0.02V increments) doesn't help, then I leave it at that higher voltage and increase Vtt the same way... once stable you can try lowering voltage (say it got stable while raising vcore, try lowering vtt a bit) this will save power and heat.

Oh and about your pic speed, EIST lowers the multiplier at idle for power saving, and C1E/C states drops the voltage/disables cores hence why you're at 9x multiplier and 0.858V. LLC is a bit risky, it can cause short burst overvolting as it tries to stabilise the vcore. With LLC off, you tend to get a voltage drop under load but that is within Intel's specs. I like it on, but just fyi it's not entirely safe... shouldn't have an issue with a mediocre OC but high Vcore with LLC can potentially be dangerous.

 

[moe112]

Best answer selected by moe112.