I5-2500k/asus p8z68-v/gen3 multiplier jumping like crazy

[VARJAG]

Hello. I might have a problem or it's just something I've never encountered before. I just bought Intel i5-2500k and asus p8z68-v/gen3 motherboard. CPU is running at stock 3.3Ghz. I have the latest bios and I loaded "optimized defaults" settings.

Before you start telling me about Speedstep - I know about IEST and than it downscales CPU to 1.6Ghz on idle and brings it up to default 3.3Ghz on load.

In my case it sort of does that, at idle it's 1.6Ghz at FULL load it's 3.3Ghz, BUT in between I'm seeing 1.7Ghz 2.1Ghz 2.5Ghz 2.8Ghz 3.1Ghz speeds. It's like speedstep is going from idle 1.6Ghz to how much it needs(1.7Ghz 2.1Ghz 2.5Ghz 2.8Ghz 3.1Ghz) instead of going straight to 3.3Ghz. I have CoreTemp gadget and CPU-Z, both showing same thing, multiplier is jumping like crazy depending on current CPU load.

Example: launching one movie - 1.6Ghz, two movies -1.6Ghz, three-four - it sits pretty at 2.6-2.8Ghz instead of going full 3.3Ghz, and only when I really start loading CPU, it goes to 3.3Ghz.

Am I missing something or is this behavior normal for this CPU/Mobo??? Help??

 

[mcnumpty23]

on my 2600k with P8Z68-V PRO/GEN3

it goes straight from 1600mhz to 5ghz

nothing in between--but i have altered the bios quite a bit to get to 5ghz so that may make it behave

differently

 

[jimmysmitty]

Thats normal behavior for the CPU at all stock settings. My 2500K does what mcnumptys 2600K does, mine goes from 1.6GHz to 4.5GHz but thats because I have changed the BIOS and disabled all power features except SpeedStep.

Yours still has all the advanced features on so it will throttle the voltage and multiplier to only give your PC what it needs to perform that task.

I also have the P8Z68-V Pro/Gen3.

 

[VARJAG]

After loading defaults I've started toying with bios. Changed AI to X.M.P. and disabled Turbo mode, C3 and C6 states leaving C1E enabled. I do not completely understand importance on C1E so I left it enabled for now(any help on C1E will be appreciated). Now my CPU is definitely not so "jumpy" but still does go to 2.1Ghz/3Ghz sometimes, is it because C1E is still on?

Also can you tell me what are "all power features" that you turned off? I turned off EPU\C3\C6, C1E is still enabled.

On the other note, should I be using software that comes with the motherboard? Or I need to delete it?, cause I don't see any use from it(except Fan Xpert) since I prefer to do all the tweaking and OCing in BIOS. It's called AI suite II.

 

[jimmysmitty]

Get rid of the software.

I killed everything except Turbo and SpeedStep, Turbo is needed to be on to Overclock.

So it is probably C1E.

Unless you are overclocking, you really don't need to disable them as they wont hurt performance at all.

 

[VARJAG]

Get rid of the software.

I killed everything except Turbo and SpeedStep, Turbo is needed to be on to Overclock.

So it is probably C1E.

Unless you are overclocking, you really don't need to disable them as they wont hurt performance at all.

Well I enabled C1E and EIST, C3/C6 are on auto which I think is disabled by default. And then I made turbo mode run at 4Ghz, when I loaded to Windows it was all good, but Vcore was around 1.33 which is ridiculously high for this clock speed... so I manually found a value of 1.15v which vorkes like a charm at 4Ghz, running Prime95 right now and no errors as of now, also my CPU temperature is peaking at 50C while it's about 20-22C in my room. Now I need to calculate offset mode so Speedstep can drop Vcore as well as core speed. And CPU multiplier stopped jumping all over the place, now it's straight 1.6Ghz to 4Ghz.

Now my question is about Load Line calibration, I left it on auto for now since this is a very low overclock, or should I use High/Extreme? And SpreadSpectrum enabled or disabled???

 

[amuffin]

Turn off everything except for C6.

 

[VARJAG]

Turn off everything except for C6.

Since I'm pretty much a noob in this sort of stuff could you tell me why, cause I a lot of guides I see C1E enabled and C3/C6 disabled??

 

[nickeverett]

I have P8Z68-V /GEN3 and 2500k, running at stock. My CPU behaves the same when I turn TPU and EPU switches on (they are on the top right of the mobo) and set the bios AI settings to auto.

If you don't like this, it can be changed by turning the TPU and EPU switches off, then the CPU goes to either 1.6ghz or 3.4ghz.

If you want more you can then dial in a moderate multiplier, say x38 to get 3.7ghz or 1.6ghz when idle.

Sorry this isn't the most precise post, but i hope you get the idea.