LLC Inquiry

[johnnyl168]

Hey guys hopefully some1 can help me out here. When I disable LLC the annoying buzzing noise from the chokes was minimised dramatically but I BSOD after 2 passes of Intel Burn Test. With LLC enabled Im very stable. Would it be more beneficial to disable LLC (increase vcore to make it stable again) in my circumstance cause of the buzzing noise from the choke or just leave LLC enabled? Which I was told the buzzing noise is normal. Thanks

Specs E6750, XMS2 pc6400 (2x1gb), ep45 ud3r and tx-650w

[Nickel020]

Re: LLC Inquiry

For dual cores I would disable LLC as it will often cause actual VCore to be lower in idle than in load which is not good.
The cause why your CPU fails without LLC is that actual VCore differs quite abit from the BIOS setting when LLC is disabled (much more then so than with LLC on). Just watch your VCore during load with LLC on then watch it without LLC and increase it accordingly until you reach the same value. Use CPU-Z to watch the VCore.
Don't worry about the larger difference between the BIOS setting and the real value shown by CPU-Z, it's perfectly normal.

[johnnyl168]

Re: LLC Inquiry

Thanks mate much appreciate the help.

[samuelmorris]

Re: LLC Inquiry

You can probably make up for the loss of disabling LLC by upping the Vcore slightly. Unless you're using a huge increase already, it should be safe enough.

[johnnyl168]

Re: LLC Inquiry

Here are the results:
Sorta don't wanna go any higher with the voltages =), any recommendations please. Also Im trying to post my BIOS settings but it wont allow me to cause its saying that Im over 10000 characters?

Intel Burn Test
LLC Enabled IDLE Load 70c
BIOS 1.425 Pass 1.392 1.392
LLC Disabled
BIOS 1.43125 Fail BSOD 1.392 1.360
BIOS 1.4372 Fail BSOD 1.392 1.376
BIOS 1.44375 Fail 50% 1.392 1.376

[samuelmorris]

Re: LLC Inquiry

The Vdroop of most boards is more than 20mV, you'll need to go higher than 1.44 to get the same stability you achieve with LLC enabled at 1.425. Not using LLC will hurt your power consumption but there's not much I can suggest. I haven't experienced any noise with LLC enabled on either of my boards, could it be a defect?

[johnnyl168]

Re: LLC Inquiry

http://forums.tweaktown.com/f69/buzzing-noise-29656/

Thanks guess ill bump my vcore a little more =(

[Nickel020]

Re: LLC Inquiry

Yeah bump the Vcore a little more so you get 1.392V under load. You CPU is a 65nm model, there are actually CPUs that come with stock voltage 1.35V there (unlike 45nm where stock is ~1.25V at most). So 1.40 isn't all that much for the CPU.
Remember that you can't compare a 65nm with a 45nm CPU. As a rule of thumb you can say that 65nm parts can take 0.1V more!

[samuelmorris]

Re: LLC Inquiry

Yeah, my motherboard doesn't seem that prone to that, but my graphics cards do.

[johnnyl168]

Re: LLC Inquiry

My stock voltage on my CPU is 1.325 (BIOS). Did you mean 1.35 in BIOS or CPU-Z?

[Nickel020]

Re: LLC Inquiry

The stock voltage varies from CPU to CPU even among the exact same voltage, some E6750s have VIDs below 1.3V, others have 1.325 like yours and some have them at 1.35V.

[johnnyl168]

Re: LLC Inquiry

BIOS 1.45 BSOD CPU-Z IDLE 1.408 Load 1.376
Meh gonna just leave LLC enabled and bare with the buzzing noise.

[samuelmorris]

Re: LLC Inquiry

Try 1.475. 3.8Ghz on an E6750 is quite high, and will require more than 1.376V under load.

[Nickel020]

Re: LLC Inquiry

Don't pay attention to what the BIOS says the VCore is, the only thing that matters is CPU-Z.
I would disable it and increase VCore until it's stable, but do whatever helps you sleep at night ;)

I'm off, have fun with your system!

[johnnyl168]

Re: LLC Inquiry

Woot finally got it stable had to raise the voltage to 1.475 as suggested to get a load reading of 1.392Thanks again for the help
Idle temps are a little higher tho 1-2c (1.424v on idle) =(