PC Under clocking my over clock

exotic444 · 17 Nov 2010 at 20:18

Hi,

Basically I just brought some new 1066Mhz ram so I can over clock to 4Ghz so I started off by increaseing the FSB by 10, worked and tested so decided to bump it up another 10 and then I loged onto PC and when OCCT was running it was saying my CPU was running at 2.8Ghz (434 x 6.5) when it should be 3.6Ghz (434 x 8.5). got no idea what is going wrong,

Here are some pics of my bios set up:

Links:
http://img831.imageshack.us/img831/7995/dsc01474xa.jpg

http://img710.imageshack.us/img710/2406/dsc01473j.jpg

Here is pic of Coretemp:

P.S also this was when running OCCT stress tester so I know its not the intel speed step thats underclocking to save voltages and heat

Voltages:
CPU: 1.27500
CPU PLL: 1.54
FSB term: 1.24
DRAM: 2.10
NB: 1.26
SB: 1.20

If anyone could help that would be nice

oh and rig is in the SIG but got new OCZ HCP reaper -pc8500 instead of the pc-6400

Frozennova · 17 Nov 2010 at 20:27

My guess would be thermal throttling due to either CPU temperature or VRM temperatures. This was solved by a rather Ghetto 120mm fan placed above the VRM heatsink

exotic444 · 17 Nov 2010 at 20:27

frozennova said:
My guess would be thermal throttling due to either CPU temperature or VRM temperatures. This was solved by a rather Ghetto 120mm fan placed above the VRM heatsink

but temps are under 55c? look at pic on core temps

Surveyor · 17 Nov 2010 at 20:49

Multiplier reduced at idle to save power.

Stress the CPU and then see what speed it shows.

Frozennova · 17 Nov 2010 at 20:53

I would suggest getting an 80mm or 120mm fan and aiming it to blow down on the area circled red in the image below. The voltage regulation circuitry on your board will get hotter than normal when you begin to overclock and raise the Vcore. Once the temperatures get too much the board will throttle back reducing the multiplyer and vcore to allow it to cool. I have a similar issue on my system where by I would be throttled back to a 4x multi for 10-15 seconds every minute or two.

EDIT:

Surveyor said:
Multiplier reduced at idle to save power.

Stress the CPU and then see what speed it shows.

OP states that rig is being stressed with OCCT to remove the chance of it being Speedstep

exotic444 · 17 Nov 2010 at 22:42

frozennova said:
I would suggest getting an 80mm or 120mm fan and aiming it to blow down on the area circled red in the image below. The voltage regulation circuitry on your board will get hotter than normal when you begin to overclock and raise the Vcore. Once the temperatures get too much the board will throttle back reducing the multiplyer and vcore to allow it to cool. I have a similar issue on my system where by I would be throttled back to a 4x multi for 10-15 seconds every minute or two.

EDIT:

OP states that rig is being stressed with OCCT to remove the chance of it being Speedstep

Thanks for the advice but I already put fan on that part, a fan came with the mobo and I knew I was going to be overclocking so I put it on.