2 approach to overclocking... and differences I found.

[Tutor]

This is the ratio that i'm suggesting that you set as low as possible while maintaing a stable system.

BUT 38 is the lowest number I can enter in this field. If I enter anything below 38, and reboot, the system just goes into a boot loop for 3x, then the system reverts it back to 38x automatically to be able to post successfully. I cannot set this number to anything below 38.

[quote:19a6oy61]set Turbo ratio (1-core) to 44x, Turbo ratio (2-core) to 44x, Turbo ratio (3-core) to 44x and Turbo ratio (4-core) to 44x,

If I leave CPU clock ratio to 38x (i.e. the lowest number I can enter in that field) then I can set Core1--4 to 44x. This is the METHOD#2 I was talking about. Using this approach, the temps are higher, the temperature swings wildly up and down.

Maybe we have a different motherboard and thus need a different approach to o/c?[/quote:19a6oy61]

Try core scaling, using 46x for core1, 45x for core2, 44x for core3 and 43x for core4. And add 1 to each until system stability is compromised; then back down a step. If you cannot go below CPU clock ratio of 38x, this means that your cpu, unlike mine, may not unlocked downward as much,so you'll have to be content with turbo biasing without the wider range of turbo that I get from being able to downclock to 13x. Mine, however, will not go as high as yours wil because mine tops out at 27x (27 - (E) 14 = (D) 13).

 

[powerpcg5]

I found a piece of information on another site, regarding this 38x mystery.

"Intel "technical support" guy and he told me that if you run 1600Mhz or faster RAM that the multiplier will go to 3.8Ghz automatically. "

I think this is the reason why I can't enter a number lower than 38.

 

[Tutor]

I found a piece of information on another site, regarding this 38x mystery.

"Intel "technical support" guy and he told me that if you run 1600Mhz or faster RAM that the multiplier will go to 3.8Ghz automatically. "

I think this is the reason why I can't enter a number lower than 38.

Opps - I forgot to point out one caveat: it appears that the highest working turbo range is E or 14 at the top end. What this may mean for you SB owners is that you may not be able to go much, if any, below 38x for the base cpu multiplier because 14 + 38 = 52 which is getting to close to the max potential of your cpu (the highest multiplier for Sandy Bridge is 57 [57 - 14 = 43]) and your bios may not let you downclock as mine does to basement nos. like 13. Mine, however, will not go as high as yours wil because mine tops out at 27x (27 - (E) 14 = (D) 13). So my max turbo range is 14 bins because setting my cpu multi to its lowest setting which is 12, make my system unstable and extremely slow. I believe that native power management cannot handle turbo bins higher than E or F, although I cannot get the F turbo ratio because setting 12 as the cpu multiplier sucks.

What's the highest no. you can enter for a turbo core value?

I don't know whether lower you memory speed to get below 38x will be worth it. You'll have to determine that in your experimentation. But try turbo scaling the cores with 46x for core1, 45x for core 2, 44x for core3 and 43x for core4, while keeping your cpu frequency ratio at 38x and tell me how that affects your Vcore needs, temps and geekbench2 score. You might also try jagged turbo scaling/skipping settings of 41x for core1 , 51x for core2, 42x for core3 and 50x for core4, leaving cpu frequency ratio of 38x. This can be fine-tuned if you can closely monitor your core temps using either bios or a 3rd party core temp measuring tool like iStat, but assigning to the coolest core (using the same turbo ratio no. for test purposed to determine which of your cores are relatively the hottest and which are relatively the coolest when they run at the same speed) the highest turbo ratio and assigning the next highest ratio to the 2nd coolest core, etc. - just food for thought.

 

[powerpcg5]

I was able to enter 16x on the cpu clock ratio.... but at the expense of lowering DDR speed to 1333. Then I could enter 47, 46, 45, 44x for the different cores.

But running at 1333 hurt performance. Not worth it .

So in the end, method#1, the numbers still came out better, I think is the best method for this particular SB system and mobo... i.e. 44x cpu clock ratio, and just AUTO setting for Core1,2,3,4 running @ 1600Mhz DDR3.

I'm gonna lay this to rest. Happy with my results with method#1.

 

[Tutor]

I was able to enter 16x on the cpu clock ratio.... but at the expense of lowering DDR speed to 1333. Then I could enter 47, 46, 45, 44x for the different cores.

But running at 1333 hurt performance. Not worth it .

So in the end, method#1, the numbers still came out better, I think is the best method for this particular SB system and mobo... i.e. 44x cpu clock ratio, and just AUTO setting for Core1,2,3,4 running @ 1600Mhz DDR3.

I'm gonna lay this to rest. Happy with my results with method#1.

I regret that my last suggestions such as your trying turbo scaling the cores with 46x for core1, 45x for core2, 44x for core3 and 43x for core4, while keeping your cpu frequency ratio at 38x and memory at 1600mhz didn't work out.

 

[powerpcg5]

No problem.

Hey, we learned something new today. SB systems don't allow base cpu clock ratio lower than 38 if you're using 1600Mhz RAM speed. Why.... only Intel knows.