Core i7 Overclocking Guide For Beginners

[Mokuso]

Cool, does Prime95 test the mem modules as well? Or will I have to use a dedicated tool for that? I've seen Memtest come by a couple of times?

[Clunk]

For what we are doing here, prime95 is enough. You can set the torture test to be Large FFTs which will test more memory, or small FFTs which will test the CPU more, or blend which does a bit of everything. Generally though, just use the blend test and it'll unearth most instabilities.

Probably the best way of stress testing is to run your most intensive applications for a day or so.

Personally, I'd leave memtest for diagnosing faults.

[Mokuso]

Thanks, that makes heap loads of sense. Hmmm. Time to get back into the BIOS...

[BalloonBoy]

I have a i7 920 C0 CPU. I followed your 3.3 Ghz settings with 8-8-8-20 timing for my OCZ3X1333LV6GK (3x2GB) kit. Prime95 blend test BSODed the system within two minutes. I upped the CPU voltage from 1.10 to 1.11. Then the prime95 crashed within 10 minutes. I notched up the voltage to 1.12 and it ran fine for an hour at 57'c before I stopped the prime. I am just curious as to what the CPU voltage is for 3.3 GHz with D0.

What's the safest / intel recommended i7 CPU voltage?

Also, I tried to run Everest but my windows 7 x64 reboots immediately. Does that mean I have some hardware problem?

[Clunk]

Please add your full system specs to your profile so we can help you further. See my sig for details.

[Adunaphel]

Hi Clunk.

Thank you for an excellent job on the guide and for you regular, patiently provided, support to OC beginners. A big thank you to the other regular posters as well.

To begin, I have not received my pc just yet (arriving this coming Saturday) but I was hoping to shoot off some initial questions. I think I have successfully added my ‘potential’ system spec to my profile - as you frequently request.

Here goes:

1) When I ordered my PC from Cyberpower I asked for a i7 920 "D0 step" CPU and want to verify that is indeed what I was sent (as opposed to a C0/C1). Is there an easy way to do this without taking off the CPU cooler and looking at the serial number?

Now to the OC part (after I have a stable 4Ghz on CPU – or as high as I can get with a CPU voltage of 1.25):

2) I ordered 6GB of 2000MHz memory and I am not 100% sure how to setup my bios as your guide is for 1600MHZ memory.
a) At some point you mentioned we should start with DDR3 - 1523MHz (for 2000MHz memory) until we have a stable system and then change the memory settings. What do I do from there?
b) Do I need to reset the bclk to 133Mhz and find a stable memory OC?
c) Will I need to change Uncore or QPI multiplier in any way? If not is there a benefit in changing the Ucnore/QPI anyway?
d) If I set my bclk to 200MHz (for a 4GHz OC) and memory multiplier to 10x will that reach by stock memory speed of 2000MHz? What is a good low to average limit for memory OC. Is it really worth it, seeing as benefit is so limited?
e) If I do not get a bclk of 200MHz can I increase the memory multiplier to 12x? How much above stock should I try – not sure I want to get too many BSOD.
f) For a memory multiplier of 10x will I need to set the Uncore Frequency to 21x? What bout QPI?

[Clunk]

1) When I ordered my PC from Cyberpower I asked for a i7 920 "D0 step" CPU and want to verify that is indeed what I was sent (as opposed to a C0/C1). Is there an easy way to do this without taking off the CPU cooler and looking at the serial number? Download CPU-Z and run that, it will tell you on the CPU page.

Now to the OC part (after I have a stable 4Ghz on CPU – or as high as I can get with a CPU voltage of 1.25):

2) I ordered 6GB of 2000MHz memory and I am not 100% sure how to setup my bios as your guide is for 1600MHZ memory. Until you get to grips with the new system, just treat it as 1600MHz as per the guide, you can always up the memory speed later, although running at 2000MHz won't really seem any faster than 1600MHz to be honest.

a) At some point you mentioned we should start with DDR3 - 1523MHz (for 2000MHz memory) until we have a stable system and then change the memory settings. What do I do from there? It's just a case of finding out where you CPU will go and then getting the memory as close to its rated speed as possible by upping the memory divider. You can also use a lower multi and a higher BCLK if your CPU will do it.

b) Do I need to reset the bclk to 133Mhz and find a stable memory OC? No, just find the CPU's max first.

c) Will I need to change Uncore or QPI multiplier in any way? If not is there a benefit in changing the Ucnore/QPI anyway? No and no.

d) If I set my bclk to 200MHz (for a 4GHz OC) and memory multiplier to 10x will that reach by stock memory speed of 2000MHz? What is a good low to average limit for memory OC. Is it really worth it, seeing as benefit is so limited? See above.

e) If I do not get a bclk of 200MHz can I increase the memory multiplier to 12x? How much above stock should I try – not sure I want to get too many BSOD. Wait and see what your CPU will allow when you get it.

f) For a memory multiplier of 10x will I need to set the Uncore Frequency to 21x? What bout QPI? Again, don't worry about these, AUTO is where they should be. QPI voltage will need upping to run 2000MHz memory though usually.

Welcome to the forums

In a nutshell, get the system, make sure it works ok, then do the CPU first as per the guide, once you are happy and have got the hand of how it all works, you can do the memory.

Please send the suitcase full of used bank notes to the usual address

[Adunaphel]

Hi again and thanks for reply.

Just had a stable run with the following:

Ai Overclock Tuner - Manual
CPU Ratio Setting - Auto
Intel (R) SpeedStep (TM) Tech - Enabled
Intel (R) Turbo Mode Tech - Enabled
BCLK Frequency - 190
PCIE Fequency - 100
DRAM Frequency - DDR3 - 1523MHz

CPU Voltage 1.3125v
CPU PLL Voltage - Auto
QPI/DRAM Core Voltage - 1.3v
IOH Voltage - Auto
IOH PCIE Voltage - Auto
ICH Voltage - Auto
ICH Voltage - Auto
DRAM Bus Voltage - 1.65v

Did not adjust DRAM CAS or DRAM RAS yet.

Problems:

1) I am running at a temp of 88c peak (85c average).
2) My crappy coolit domino is on full fan speed and as you correctly noted, it sounds like a hair drier.

Next steps:
Scale down the vcore to 1.25 and see if coolit domino can stay under 75c on medium fan speed!
I will try a bclk of 180 to begin and drop to 170 if necessary

[Clunk]

To be perfectly honest, the Domino isn't really designed to dissipate the heatload of an i7. There's not a great deal you can do one the temps start spiralling either, short of changing it for something else.

[Adunaphel]

Won't change it - spent enough money as it is...will just settle for a lower OC.

What DRAM timmings do you recommend for the dominators?

8-8-8-24?