Quick quesitons about undervolting the 6970M...

What's the stock voltage of the 6970M and is there a noticeable difference in TDP before and after dropping the voltage down?

Got a second 6970M incoming and I was wondering this since the R2 only uses a 240w PSU as you all well know.

 

6970/6990's have a stock voltage of 1.1 volts.

Hard to say, I can't recall anyone giving actual figures. All I know is that it certainly can make a difference if you are experiencing throttling.

Now, if this is because it greatly reduces current draw, or because the R2's with 69XX cards are right on the line of maxing out the PSU, I am not sure.

I dont think you will have much of an issue if you are running your 920 at stock. However if you want to overclock your 920 then you may need to undervolt the 6970s.

People have had successful undervolts of 0.96v, but this will vary depending on your cards. You will be able to undervolt, the question is just, how much

 

I won't find the need to overclock anything, but if undervolting does help with the TDP even by a factor of 5-10w per card, I'd be more than willing to undervolt both GPUs.

Anything that would give me a bit more stability in the end. Last thing I want is to pop this PSU...

 

I wouldn't worry about the PSU that much, it has safety built in to stop any real damage occurring.

Your main objective is to thwart throttling.

Also, it is important to remember that undervolting can sometimes cause instability. Even if it seems stable for a while, it can start playing up further down the line and mean need some more juice.

Good Luck!

 

I had a temp reduction of 4-5 deg C on 0.96V