If you are going to upgrade the motherboard, then do the memory and the CPU cooler as well which would put you in a much better position to clock
Motherboard
Best
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131284Good
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131219Memory
http://www.newegg.com/Product/Product.aspx?Item=N82E16820145197or
http://www.newegg.com/Product/Product.aspx?Item=N82E16820146785CPU Cooler
http://www.ocztechnology.com/products/cooling_products/ocz_vendetta_2_cpu_coolerIf you are going to change the motherboard then upgrading the memory would be the way to go at the same time so you can get the perf ot of the system. Memory is critical. To run 1066-1080 at 5-5-5 with 400-450MHz FSB as I outlined to Vic you need the right memory product
The QX6850 is a 65nm processor.. its max speed is going to be 3.6GHz. Because its a QX processor the multiplier is available. That is what you pay 1000 bucks for, the multiplier. You did not have to pay 1000 dollars if you did not intend to clock. The Q6700 is the EXACT SAME processor sold for 250 bucks
Unlike the QX68, the Q96 does NOT allow multiplier changes, therefore the STOCK multiplier is locked and you must use 9 for ALL calculations with a Q96 and, you use FSB to increase the CPU speed. The QX6 allows you to increase or decrease the multiplier and therefore you can run faster CPU speeds without changing the FSB which is why they cost 1000+ dollars. It allows pinpoint clocking adjustments where other procs do not.
You paid for the access to the multiplier. Right now because you paid over a grand for that chip you can go into the BIOS and set the CPU MULTIPLIER to 10 instead of 9 and run 10x333 or 3.33GHz probably without touching the vcore voltage. To hit 3.6HGz you would need to raise the CPU VOLTAGE or vcore voltage and have a heatsink able to handle the heat. A QX6850 will require 1.44-1.45v vcore with the CPU VOLTAGE DAMPER -or- LOAD LINE CALIBRATION (if the BIOS has one of those settings available) ENABLED to run 3.6GHz
It may or may not do 10x333 without a slight increase in CPU VOLTAGE. That is a trial and error check and setting.
The primary goal is to find the stable clock settings on the right voltages. If you purchase the parts I listed above the settings I posted for Vic on the first page of this thread for his Q6600 and DDR2 1066 memory are exactly the same for you, except.. because you have a QX processor you can try an even better clock than he had.. 8x450MHz = 3.6GHz @ CPU STRAP 400 and 1080MHz memory speed
I know for a fact the first motherboard I posted will do that and the 2nd one I have seen do 450MHz too.
So with the QX6850 you can run 9x400 = 3.6GHz @ 400 STRAP and 1066 5-5-5-15 -or- change the multiplier and run 8x450 = 3.6GHz @ 400 STRAP and 1080 5-5-5-15 with then memory and motherboards posted above
In both cases the vcore is set to 1.44 or 1.45v and the memory voltage is set to 2.1v... same settings I posted to Vic
As for temps and stability stress testing..
http://www.ocbase.com/download.php?fileext=exe OCCT a CPU and system stress test software
http://www.alcpu.com/CoreTemp/ monitor the CPU core diode temps
Use the software OCCT 1 hour AUTO test with the software CORETEMP. If the processor or memory is unstable that test will show it. That test will also run the CPU core temps SKY HIGH and that is the 2nd goal to be sure the temp of that QX6 remains below 75c for the entire hour of the test... if it doesn’t then either:
CPU heatsink was not installed correctly or too much thermal compound
Tower itself does not have proper venting fans
Vcore too high (never exceed 1.50v CPU VOLTAGE)
NOTE: You may need to manually set the MAX CPU temp in OCCT to 75-80c so the test does not halt. Sometimes that value is set too low by default in the OCCT properties.
That test will stress and heat the CPU far more than FSX or any other application will therefore if the test passes and the temp remain below 75c, your fine
Every processor has a different temp range its safe to use. The 65nm QX series is below 80c DIODE temp. There is a difference between the CPU CASE and CPU DIODE temp,.. the CPU CASE TEMP is usually 15c LOWER than the REAL CORE TEMP which is why one must use special software (as I posted above) to read the TRUE CPU DIODE core temp.
That software will show the value tJ-MAX. tJM is the POINT OF NO RETURN temp of the processor. For the QX6 that 'should' be 100c. Your processor starts to automatically shut down well before that temp however there is another value called tJunction which is the BEGINNING of where the proc begins shutting down. That value is typically 20-25c LESS than tJMax. Therefore we test for max heat and stability using a max allowed diode temp of 20-25c LESS than tJMAX
The Q9650 (wihich is a P-QUAD) is DIFFERENT for CPU VOLTAGE! With a Q9650 you NEVER exceed 1.36v. It will also clock to 4050MHz IF you can set the motherboard to 450FSB and be stable. 9x450FSB = 4050 9x400FSB = 3600
To do 4050 you will definitely need that CPU cooler I listed. You can not use the Intel CPU cooler to clock those processors much past 3.4GHz. It may be possible to run 3.6GHz on the Q9650 with the Intel CPU heatsink.. that, I am not sure. You would need to test it as I specified above however any person who clocks knows the fatory heatsinks are really shit.
For 4050MHz (4GHz) the CPU vcore will be right around 1.28-1.32v. For 3.6GHz it will be 1.28v or less.
The temp spec is the same... max load 75c in coretemp
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