Im trying to overclock my system to save some time on a really high poly renderings
my specs are
I7 940, 12GB ram 1033mhz, Asus PT6 MB
i did a search on google with those specs and found some one who used those settings
Ai Overclock Tuner - Manual
Cup Ratio Setting - 20
BCLK Freq - 178
DRAM Freq - DDR3 -1427Mhz
QPI Link Data Rate - 6424MT/s
CPU Voltage - 1.32500
CPU PLL Voltage - 2.00
QPI/DRAM Core V - 1.32500
DRAM Bus Voltage - 1.64
gets me 3.57Ghz ~
i did some renders and left it for a day and everything is running great, no crashes
now i wanna get even more but i donno what parameters to change and by how much
can u guys tell me what to change to get better speed?
Replies
You can get more speed for CPU bus frequency without a doubt.But you must decrease your RAM speed,really worth it.CPU speed is always more important.
And what's the tempature at load and idle?Its too important to say how much you can go.You'll need a cooling solution at the higher speed for reliability.Also might be reduces the fan noise.
the temp is 48c which is good i think,
From my own experience:
1) Odd numbered CPU multipliers are more stable so you could increase the multiplier to 21x (discovering this was the most interesting thing I came across and very few sources I found mention this.)
2) A BCLK frequency of 178 should be sufficient, you'll be getting a cpu speed of 3.74GHz which is good.
3) From what I can see your RAM has a multiplier of 8 which I think is the minimum for DDR3 RAM but if you can drop the multiplier then go ahead.
4) If you have sufficient cooling which means high-end air coolers or even a water cooling system for the cpu you can raise the voltage to 1.35V although it's quite risky and if I were in your place I would raise it in the smallest possible increments IF the system is unstable.
5) A 15 minute Prime95 test in Blend mode should be sufficient to show how stable your system is. You could even leave if for 30 minutes but be sure to keep track of temps and make sure the temps stay under 100C.
6) Get better RAM, one that has a default speed of 1333MHz without overclock so you can drop the RAM Bus multiplier to 8 and it would stay stable because it would reach something close to or below 1333MHz which the RAM was already designed to run at. I think you see what I mean.
RealTemp is one of the best programs to keep track of temperatures. Make sure your temperatures stay below 100C. 105C is when the CPU undergoes thermal shutdown to prevent damage and you should be as far away from that temperature as possible.
WARNING: I am not responsible for any damage to your system. Be sure to research other people's overclocks of the i7 940 before going anywhere near the voltage controls.
64-Bit Prime95
32-Bit Prime95
RealTemp
RAM's are very sensitive to OC'ing, because you have to remember that you're also playing with electricity when OC'ing (EI: pumping extra heat and juice in a hardware which has a certain threshold).
Imagine a Tank if you will, that Tank has a certain amount of heat tolerance it can take before the hardware give out, and PC's are no different. You'll need to calculate also what ratio of voltage is hitting your other component on your mother board not to fry anything.
There are some good OC calculators out there, which will tell you how much each part can OC'ed safely, as well if you should with your current motherboard.
One personal question I have to ask, do you really need the extra juice power to render? Did you try a render test both OC'ed and stock to see if there were any major differences? I know in my case, OC'ing usually nets me about 5-10 seconds per render, however, if I'm pushing out really high end shaders and polies, I barely get back 2 seconds max. So investing in a better processor which has more cache and cores, it usually a better deal.
http://www.clunk.org.uk/forums/overclocking/22106-core-i7-overclocking-guide-beginners.html#post64374