CPU slower when GTX560 installed

[kzt50]

Hi,

I recently installed an ASUS GTX560 graphics card and noticed that the speed of my CPU has dropped (according to CPUZ and Speccy).

I have a Q9400 2.66Ghz, 4 GB DDR2 and a Gigabyte Motherboard, Windows 7 64-bit. I had overclocked the CPU to 3.2Mhz but after the install noticed that the CPU was running at 2Ghz when idle. I tried overclocking again but only managed to get to 2.3Ghz.

Any ideas? Is it a PSU problem, I have a 700W but have 4 hard disk drives installed.

Regards
Kevin.

 

[RiseAgainst]

i think the power supply should be ok, could be the limitations of your motherboard not to sure though

 

[Avathar77]

2.66Mhz,2Mhz and 2.3Mhz speed CPUs I have not seen recently do you mean 2.66Ghz,2Ghz and 2.3Ghz?

Can you post a screen of the CPUz?
Have you reset the bios after installing the GPU?
Is it just because of C1E and EIST kicking in?

 

[Muel]

That system will be pulling 350W tops, unless the CPU is dying then there's nothign wrong with it.

Run a CPU stress test, then watch the speed. If it goes up to 3.2ghz again, then it's just Speedstep doing its job.

 

[kzt50]

Hi,


Disabled Speedstep and this worked.

Thanks all.

Kevin.

 

[Limpnoodle]

Why disable speedstep? leave it on and save a few penny's on ur leccy bill

 

[kzt50]

Hi,

I can overclock to 3.4Ghz with speedstep off.

 

[linktoinsanity]

Hi,

I can overclock to 3.4Ghz with speedstep off.

Speedstep allows a higher speed when u need it still though, the max cpu speed will still be 3.4Ghz...

 

[James J]

Speedstep allows a higher speed when u need it still though, the max cpu speed will still be 3.4Ghz...

Yup

My i5 2500k is at 1.6ghz when I'm just browsing the OcUK forums but as soon as I start playing a game or editing photos it jumps back to 4.5ghz (overclocked of course!)