CnQ / C1E not working during overclock?

[wanner]

Hi,

I have a Gigabyte 890gpa-ud3h and a Phenom II X4 955BE C3.

First of all I would like to say that I know its recommended to turn off Cool & Quiet and C1E while overclocking. However, I would still like an answer to my question if possible.

At the moment im running my CPU at 3700MHz and C1E/CnQ is working fine. CPU frequency and voltage is lowered when the CPU is in idle. However, if I increase my overclock to 3800MHz it seems that they C1E/CnQ arent working anymore (im not sure which one?). The CPU wont declock during idle.

Any idea why this is?

Thanks!

[Dark Mantis]

I would think it depends on how you increase your overclock and do you have to bump the voltage at the same time?

[wanner]

I would think it depends on how you increase your overclock and do you have to bump the voltage at the same time?

I overclock it in BIOS by increasing the multiplier.

At the moment im running
18.5 * 200MHz = 3700Mhz
1.35V

If i increase the multiplier to 19 and keep the voltage at 1.35 C1E and CnQ wont work anymore...

[Dark Mantis]

Well I am not the expert on this platform so I don't want to give you duff info but I think you still have a bit of headroom as far as voltage goes. Absic would be the one to tell you I am sure.

[wanner]

I have tried increasing the voltage to 1.4V without any result (except higher temperatures). CPU will still not declock (is this the correct term?) during idle.

[wanner]

Seems im not alone with this "problem". Found thread, http://www.overclock.net/amd-cpus/687998-cool-n-quiet-wont-work-anymore.html

[Dark Mantis]

Interesting read. It would seem like you have hit the ceiling. I really don't know why it has been written that way except possibly just in error.

[wanner]

Seems to differ depending on which motherboard you have. 3.8GHz seems to be a common ceiling, but I have seen people report that it works above 3.8 as well. And some says that CnQ is disabled as soon as they change the multiplier.

[Dark Mantis]

As I say absic might have more information on it but I can't help any more, sorry.

[wanner]

As I say absic might have more information on it but I can't help any more, sorry.

It's ok. Im experimenting with this and are just sharing my finds at the moment .

I tried lowering the multiple to x17.5 and increased the FSB to 220Mhz, resulting in an overclock at 3850Mhz, and Cool N Quiet seems to be working fine with these settings .

[absic]

Hi there,

to be honest I don't know the answer to this one as I never use the CnQ and it's always one of the first thing I disable in BIOS.

Reading through the article you linked to and it seems pretty common and annoying as it maybe, I think it is designed that way to try and protect the CPU.

[wanner]

It seems that the limit is not tied to the frequency but the multiplier. In my case CnQ wont work when i increase the multiplier to x19, but x18.5 will work just fine. But as i mentioned in my previous post, by lowering the multiplier and increase the FSB it will work just fine. Of course this means that when CnQ kicks in and downclocks to x4 the frequency will be 4 x 220 = 880MHz instead of 4 x 200 = 800MHz which is standard.