Getting a Q6700 to 3 GHz

[flymoop]

Hi,
I have a P5Q Pro with a Q6700 at stock speed. Memory is OCZ 4GB DDR2 1066MHz/PC2-8500. What do I need to change to get the best performance? Never overclocked before, so some simple instructions would be much appreciated!

 

[saaiello]

http://www.tomshardware.com/forum/240001-29-howto-overclock-quads-duals-guide

Everything you need to know is in that guide now go read it and then come back with any specific questions or concerns and be specific about what you dont understand and i will help you understand things a little better.

 

[jonpaul37]

SAAIELLO is right, read through that guide, it will serve you well. As for specific settings, all motherboards & CPU's and RAM are different, even if it is the same. For instance, some Q6700's can overclock higher than other Q6700's even on the same exact motherboard & cooling solution.

Couple questions that may help us...

What kind of CPU cooling do you have? is it stock or aftermarket?

The RAM you have, is it 2 x 2GB or is it 4 x 1GB? Motherboards have been know to be a little finicky when overclocking with 4 individual sticks of RAM as opposed to 2 sticks...

I have a VERY similar setup as you so i can relate.

 

[jsc]

The other thing to look for is an OC guide for your specific motherboard. Why reinvent the wheel?

Google is your friend.

 

[flymoop]

Got CPU running at 3GHz by changing bus speed to 300, and leaving rest on auto, seems fine, though I do have a couple of questions.

What should be the max difference between core temperatures? I'm using an Arctic Freezer 7 Pro, and at rest core temps are:
Core 0: 38
Core 1: 42
Core 2: 33
Core 3: 33

Seems to be alot of difference?

Also, I'm unsure what settings I should be using for my memory. It's OCZ Reaper DDR2 1066, I tried changing the DRAM frequency, but was unsure of timings to set etc.
CPU-Z currently reports it as:

DRAM Frequency: 500MHz
FSBRAM: 3:5
CL: 5
tRCD: 5
tRP: 5
tRAS: 15
tRFC: 54
CR: 2T

Any more info needed? Thanks for help so far!

 

[jonpaul37]

the temperature differences are actually quite normal, my Q6600 @ 3.6 is similar:

Idle temps using Xigmatek HDT s1283
Core 0: 35
Core 1: 35
Core 2: 28
Core 3: 29

Load Temps using Xigmatek HDT s1283
Core 0: 59
Core 1: 58
Core 2: 51
Core 3: 52

This basically means that the first two cores are being worked during normal processes and the other two are not being utilized at that time. Best way to test is to use a CPU stress-testing program (one that can stress test quad core CPU's) and monitor the temps while testing, they should be much closer when all cores are in use.

As far as the RAM goes, DDR2 1066 is just good DDR2 800 RAM that is overclocked. I like to run a 1:1 ratio as i have my CPU @ 400 FSB and RAM (being DDR2-800) is defaulted @ 400 MHz

 

[flymoop]

Running Prime95 on all 4 cores gives me:

Core 0: 54
Core 1: 56
Core 2: 47
Core 3: 47

I lowered my Core voltage to 1.25 which has dropped temp a bit, but there's still a lot of variation between cores, need to re seat HS?

For the RAM, what would I set for a 1:1 ratio for my setup?

CPU = 3GHz @ 10x300

Cheers!

 

[jonpaul37]

you would set the RAM to 300 MHz as opposed to the 500 MHz you have now but you don't have to, the 1:1 ratio is just a preference of mine, if i had my FSB @ 300 like you, i would still keep my RAM @ 400 Mhz.

As for the varying temps, i wouldn't sweat it, just as long as you don't go over 65 celcius for long periods of time you will be fine.

 

[jonpaul37]

Running in 1:1 mode is termed, “synchronous mode.” If you use a higher frequency, you’re running is so-called “asynchronous mode” which offers marginal speed advantages at the price of more heat and power consumption on a C2D/C2D Quad-based system for most users. Depending on your chipset, running in an asynchronous mode may require more vcores to some of your motherboard components such as the NB, IHC, and/or FSB Termination

 

[flymoop]

Thanks for your help, much appreciated.
So I should change DRAM Freq to 400MHz or leave at 500MHz? Is there any improvement I can get on 5-5-5-15? I'm not too sure what that refers to, and what equates to 'better' for RAM.
How would I know if vCores need a boost? Think they're set to auto at the moment.
Cheers

 

[jonpaul37]

well, the RAM frequency is rated @ 1066 (which = 533 x 2) and the 5-5-5-15 timings are default at 1066 speeds. in the case of RAM, the lower you go on the timings, the better, you could try 4-4-4-12 and see if that works, if it does not, you can lower the frequency from 500 MHz to 400 MHz and try 4-4-4-12.

 

[flymoop]

Is there a reason why the BIOS doesn't give me the option of 533, just 500? Also, which timings would I be changing in the mobo as there are about 3 different sets of 5 settings IIRC.
Cheers

 

[jonpaul37]

you have an ASUS P5Q Pro? I'll mess with my settings tonight when i get home and post back.

 

[flymoop]

Yep P5Q Pro!

 

[jonpaul37]

Ok, the BIOS did not give you an option of 533 because you have the FSB set @ 300, it will give you options based on what your FSB is set to, it's looking for a ratio. If you change your ratio to 266, you will see a 533 option for FSB, try that out just to see...

 

[flymoop]

yup FSB of 266 gives 1066 DRAM Freq, 320 gives 1067.

 

[jsc]

yup FSB of 266 gives 1066 DRAM Freq, 320 gives 1067.

No

Definition time (attention purists, I'm talking about DDR2 and I'm simplifying a little ):
Core2 CPU's use a frontside bus (FSB). The FSB is a thing with two main characteristics: speed which is usually defined in MHz and width which in the Core2's is 64 bits wide. We are concerned with the speed.

Using the Q6600 as an example, the FSB frequency is 266 MHz. The matching DDR2 memory clock for that frequency is 533 MHz (266 X 2). DDR2 memory transfers two chunks of data for each bus cycle, hence double the frequency. So, to run 1:1 at an FSB of 266 MHz, we need DDR2-533 RAM. What CPUZ does is a little confusing. It will tell you that the memory frequency is 266 MHz for a 1:1 ratio.

The FSB clock is 1066 MHz (266 X 4). The bus is "quad pumped". It transfers 4 chunks of data into and out of the CPU each bus cycle. So each FSB cycle generates 4 FSB clocks.

Now, if you increase the FSB frequency to 333 MHz, the corresponding memory clock is 667 MHz and the FSB clock is 1333 MHz.

I always run my memory at 1:1. That is the FSB freq to mem freq ratio of one to one. That means that the memclock is twice the FSB freq. It's a little confusing. Running memory slower costs performance. Running memory faster does not give you much if any real world performance increase and it can lead to higher instability.

Some of us discuss that here:
http://www.tomshardware.com/forum/251715-29-ratio-myth

You will gain more performance by tightening memory timing than you will by trying to overclock your memory. The performance gain will not be visible without a good benchmark for memory i/o.

 

[flymoop]

Thanks for your reply,
So for my current FSB frequency of 320, to maintain a 1:1 ratio with my DRAM I would want the memory clock to be 640 MHz? My stock memory frequency is 1066.

Is this right? Also, how will I tighten memory timings?