Question(s) about my OC

[thestrangebrew]

I OC'ed my i5 750 to 3.6ghz simply by changing the bclk to 180 and turning off turbo mode or speedstep (can't remember which one right now) and if I'm not mistaken my RAM timings automatically went from 9-9-9-24 to 8-8-8-24 (I think it's at 24). My question is: Based on the increased speed, should I have increased my vcore? Things seem to be stable right now. I've ran IBT 10x and I didn't get any errors, memtest 1 pass with no errors, and prime 95 for about 4 hours without any errors. Is my cpu working harder with less juice and therefore the life of the cpu is shortened more dramatic? Also, when I ran IBT, I got around 52.6 gflops(?) on avg. Is this good?

i5 750
asus p7p55d pro
w7 64bit
8gb gskill ripjaw 1600
evga 570gtx sc
antec gamer 750w psu

 

[wolfram23]

Hi,
I've got the same CPU and motherboard as you so I think I can help a bit.

First off about vcore. If you didn't touch it then that means you're on Auto, in which case the board is pulling values off a table and essentially automatically increased the voltage. I suggest you run HWMonitor while doing IBT and see the min/max Vcore. I then suggest you go back to the BIOS and set Load Line Calibration to enabled, and set the Vcore to the minimum value you saw in HWMonitor. Test from there. If it passes, lower it a bit and repeat until unstable. This will get you the lowest voltage and temps.

Secondly, your RAM timings went down while the speed when up. This is... unusual, but depends on the settings. Your 1600mhz RAM is meant for 9-9-9-27? If they went down to CL8, then you probably dropped a bin to 8x (1440mhz). This obviously is not optimal. You might consider running at 200 base clock, with 8x RAM multiplier and 18x CPU multiplier.

52.6 Gflops is ok. I'm around 60 (little more?) at 4ghz on my 750 (FYI, 1.32V if I recall correctly). I've run up to 4.3 ghz as you can see in my profile (CPUZ validator) which I think was high 60s. I just ran an i7 2600k at 4.6ghz the other day and it was at something like 110 Gflops lol. Not that that matters...

One more tip, if you increase the IMC voltage it will also help stabilize the CPU. Generally you should pretty much increase it as much as the CPU so it's always around 0.1V less than Vcore. It also should be no more than 0.5V less than DRAM voltage (if you have 1.5V RAM then you're fine, but for example I run 1600mhz CL8 RAM at 1.65V so I need 1.15V or more IMC. I think I'm at 1.21)

The only other thing is, how are your temps? Under high stress (IBT) it should definitely be under 80. Mid 70s is ok since under regular usage it'll be less than that. You really don't want it over 70 under regular usage (gaming, video encoding, etc).

EDIT: actually I thought of more. Turbo boost will be disabled by default as soon as you go below 20x multiplier, but I suggest you leave Speed Step enabled as it will downclock your CPU at idle and save power (as well as extend the life). I also just want to say that I've done overclocking with Turbo enabled and was able to achieve 177 base clock, so you do have an option to OC with that if you want to go with a little lower clock. I also suggest if you do go for that, you turn LLC off.

 

[thestrangebrew]

Wow thanks for responding so quickly. Sorry I can't remember all the info right now, but I'll double check when I get home tonight from work. During tests, temps never got over 69 an any core and for gaming I'm not too sure. Idle it sits around 32 though. I'll try and do what you've suggested tonight and post back!

 

[wolfram23]

Yeah no problem. Check it out and let me know how it goes.