2500k / Z68 troubles, and possible warning to CPU-Z users...

[equazcion]

It took a while to find and disable all the power-saving features that would cause my CPU to report a lower multiplier and clock speed. I thought I got them all, but listen to this:

CPU-Z shows my multiplier at 40x, bus at 100MHz, and my clocks at 3990MHz.

ALL other software shows 3390MHz, or below. And I've tried many different programs.

PC-Wizard shows an interesting clue: While it finally reports my multiplier correctly at 40x (while also dumbly saying my multiplier is LOCKED at 33x max, FYI), it also shows that my CPU bus speed is down to 82MHz. In bios, my bus speed is set to 100MHz.

A bus speed of 82MHz with a 40x multiplier would yield 3390MHz, so I have to think PC-Wizard is being the most accurate here.

It would also mean that CPU-Z is being entirely incorrect in saying the clocks are @ 3990MHz, using a reading of the bios setting rather than a live sample to determine the current effective clock speed.

Can someone confirm if my thinking is correct here? Are people who use CPU-Z to confirm overclocking success actually getting inaccurate readings, and their CPUs are really running at stock speeds because some Intel feature is dropping down their CPU bus to compensate for the higher multiplier?

PS. I disabled C3/C6, C1E, EIST, and Turbo, and this is still happening. Am I correct in ascertaining what's happening here? If so what could be causing it?

 

[4Ryan6]

My ASRock Extreme Tuner reports exactly the same results as CPU-Z, you may have a bad motherboard have you considered that?

 

[equazcion]

Yes I have. But even if the motherboard were bad and CPU-Z were accurate, shouldn't it accurately be reporting the motherboard problems, ie. the lower bus and clock speeds?

I checked Gigabyte's Windows software (Touch Bios), and it reports the same as CPU-Z. I'm not sure what to believe. I'm hoping it's all the other software that's inaccurate...

 

[4Ryan6]

You haven't mentioned any voltages or settings regarding Load Line Calibration, I'm not familiar as to Gigabytes BIOS references to dealing with Vdroop, but ASRock gives various levels to set the LLC.

You'll need to use the settings that allow the least fluctuation of voltage from BIOS actual to Operating system voltages on the run side of the picture.

I've never used PC-Wizard but a 82mhz bus, would tend to be pointing to some slack operating system voltage, you're probably set allowing a lot of output Vdroop which could be causing weird readings out in the operating system.

How does Gigabytes BIOS reference dealing with Vdroop or Load Line Calibration?

Check out my signature link to the Sandy Bridge K Series OCing All Cores, see if you still have something enabled that should be disabled.