7950 OC won't underclock

[Mad_Beard]

Hello there fellow humans!
As a replacement for my drowned 7970 GHz. I've got myself a 7950 OC from Sapphire. Unfortunately it isn't on a 7970 board so no unlocking to 7970 But this little guy still offers a lot of performance for it's price (got him for a hundred bucks). Core clock 860MHz. or so, Boost clock 925MHz. (in load I've never ever saw those 860, always running at 925MHz.). Of course I've heard a lot about overclocking this little buddy, so I went for it - reached 1050MHz. like nothing (haven't tryed more yet) but there is a pretty annoying problem I've noticed - since the overclock, the card doesn't underclock in idle. It's always running at that overclocked frequency, always, even on desktop. And doesn't matter mow much I OC it, it doesn't underclock even if I increase the frequency only by 1MHz.

Power limit set to +20%, latest drivers.
Rest of the HW in sig.

[Sir Asvald]

Hello there fellow humans!

As a replacement for my drowned 7970 GHz. I've got myself a 7950 OC from Sapphire. Unfortunately it isn't on a 7970 board so no unlocking to 7970 But this little guy still offers a lot of performance for it's price (got him for a hundred bucks). Core clock 860MHz. or so, Boost clock 925MHz. (in load I've never ever saw those 860, always running at 925MHz.). Of course I've heard a lot about overclocking this little buddy, so I went for it - reached 1050MHz. like nothing (haven't tryed more yet) but there is a pretty annoying problem I've noticed - since the overclock, the card doesn't underclock in idle. It's always running at that overclocked frequency, always, even on desktop. And doesn't matter mow much I OC it, it doesn't underclock even if I increase the frequency only by 1MHz.

Power limit set to +20%, latest drivers.

Rest of the HW in sig.

I've got the same card. Set the power limit 5-10% 

 

I've got this

 

 

 

[alexhelvetica]

There is a HD 7970 Dual-X card from Sapphire, why not install it's bios?

[Sir Asvald]

There is a HD 7970 Dual-X card from Sapphire, why not install it's bios?

How can i do that? I want to try. 

[Mad_Beard]

You won't flash it to any 7970/280X unless you have a 7970 PCB, which is not my case. Mine is a Dual-X one which has a 7950 PCB. Abdul's Flex has a 7950 PCB too.

Will try to decrease Power Limit.

[alexhelvetica]

How can i do that? I want to try. 

I assume it is exactly the same as any other HD 7950 to HD 7970 conversions.

Linus did a video on it years ago, I'd look it up!

[Mad_Beard]

Reducing power limit did only one thing - load frequency fluctuating between 500MHz. and 1GHz.

But apparently Afterburner was causing the problems, reset everything in Afterburner, opened CCC, set power limit to +20, OC to 1GHz. and it's working like a charm!

[don_svetlio]

Reducing power limit did only one thing - load frequency fluctuating between 500MHz. and 1GHz.

But apparently Afterburner was causing the problems, reset everything in Afterburner, opened CCC, set power limit to +20, OC to 1GHz. and it's working like a charm!

How did you get CCC clocks to stick - mine wants maximum performance mode and I have no idea where that setting is.

[Mad_Beard]

http://s25.postimg.org/6m02stnr3/screenshot_319.png

No idea, I'm not really familiar with CCC but I guess there isn't too much stuff you can set (related to OCing). I just hope it will save the OC settings and automatically load them on next boot, setting it over and over again at every boot will be pretty annoying.

[BigDay]

read my overclocking guide. i go over how to set your settings so that your card underclocks to conserve power. link in my forum signature