Question about CPU Stock Speeds

[timoseewho]

Hello, i'm currently using an Intel E8400 which should be running at 3.0GHz, but when I use CPU-Z to check, it skips between 1.6GHz and 2.4GHz (bus speed at ~267MHz and multiplier skipping between 6 and 9). Does anyone know what the problem might be? Thanks!

[Deleted]

That's a technology (don't recall the name atm) from your BIOS. It basically lowers the speed when it's not using/needing a lot of CPU power. If you go play a game or need more CPU power it'll go up again It's normal behavior.

[Cilraaz]

As Logicaly said, Intel uses a technology called SpeedStep (aka EIST) to slow down your CPU when it's not in use. This causes it to generate less heat, use less electricity, and prolong the life of the CPU. The only time this should be a problem is if it's stepping down while you're playing. Try checking CPU-Z while active in game.

[Wingwraith]

I always disable my EIST.

[timoseewho]

I guess the only way to tell if my CPU is automatically down-clocking for WoW or EIST is playing tricks on me is to disable that option and see, thanks guys ! To extend on that, CPU-Z shows skip between 1.6GHz and 2.4GHz both with WoW open and not, so I guess it's safe to say 2.4GHz is all that is required to play WoW?

[Cilraaz]

I guess the only way to tell if my CPU is automatically down-clocking for WoW or EIST is playing tricks on me is to disable that option and see, thanks guys ! To extend on that, CPU-Z shows skip between 1.6GHz and 2.4GHz both with WoW open and not, so I guess it's safe to say 2.4GHz is all that is required to play WoW?

Not really. When there's anything above minimal activity, EIST should stop and your CPU should go up to full clock speed. You can try to disable EIST (depending on your BIOS, it should be labeled EIST or Intel SpeedStep Technology) if you're comfortable with BIOS changes.

Also, I would suggest checking your CPU temperatures. EIST, C1E, and other C-states will kick in and back down your CPU if your temps get too high.

[Wingwraith]

C1E,

Almost forgot... disable C1E too.

[Deleted]

Almost forgot... disable C1E too.

Can you explain why though? If there's a problem with the CPU not being used to the fullest, resulting in FPS loss, fair point, but otherwise it's a very handy feature that saves electricity, lowers the heat and prolongs the lifespan. there's no point in disabling it if it works fine.

[Cilraaz]

Can you explain why though? If there's a problem with the CPU not being used to the fullest, resulting in FPS loss, fair point, but otherwise it's a very handy feature that saves electricity, lowers the heat and prolongs the lifespan. there's no point in disabling it if it works fine.

I agree. There are basically only 3 times that you should disable C1E, C3/5/7 States, and EIST: you're overclocking, you're troubleshooting, or (rarely) they're causing a problem by down-clocking/volting at the wrong times.

[Wingwraith]

I agree. There are basically only 3 times that you should disable C1E, C3/5/7 States, and EIST: you're overclocking, you're troubleshooting, or (rarely) they're causing a problem by down-clocking/volting at the wrong times.

My rig is always OC'd. Right now my E6750 is running @ 3.4 24/7 stable.
Was stable at 3.6 for a long time, but lost all my notes and can't be bothered to redo it after my cmos was cleared at some point.

[timoseewho]

Appreciate the responses! My current concern is if those settings are the culprit to my FPS drops in raid conditions (mainly 25), but i'll give it a shot and see now that I know which settings in BIOS to tweak !

[Cilraaz]

Download Core Temp. You can set it to "Always On Top" and view your CPU Frequency (including base clock and multiplier) and CPU temperature (per core) while in game. That will tell you if your CPU is down-clocking or overheating, and it beats messing with the BIOS unnecessarily.

[Deleted]

My rig is always OC'd. Right now my E6750 is running @ 3.4 24/7 stable.
Was stable at 3.6 for a long time, but lost all my notes and can't be bothered to redo it after my cmos was cleared at some point.

He's running at 3.0Ghz tho, which means not OC'd, no need to do it imho.