I don't know what really happens when you write a lower V in config than in bios... This could be proved easily by writting a very low voltage and see what happens... could the GPU be damaged?

OK, I've experienced missfunction after entering windows (the display just fucked up), having 0,850 at performance in bios is too dangerous for my gpu card, it seems that after loading ati control center the card goes to performance mode (and thus the fail). So boot at 0,950V and now I have 0,950V at perfomance too. All is working flawlessly.
I've bought another XFX 7970 same model just to have the twin. At 244€ these monsters are really cheap. Next days I'm going to lower voltage in the config file and see what I get.

The twin is goign to be checked just in case the card was narrowly better to undevolt. I'm going to keep one at stock value. I need to play BF4 guys .

I have to start undervolting one 7950 that I have also. What I've learnt is that the 7970 with "magical" values in config works very very stable at 700 Khash and at 80ºC at 100% fans with I=13. HD 7950 values were rising and falling constanly albeit using high intensity values resulting in poor windows performances (I had only one gpu).

I've read that XFX models are avoided by the community, with this post has been clearly demonstrated that 7970 (and a XFX one) is a BEAST. 7950 was considered the best option.... I feel happy to know that 7970 is much better by far.

This is the post of the year guys.

P:D: I don't have faith in undervolting my 7950....

NOW YES, it is super very clear.

Drakoin FOR PRESIDENT.

THis is PURE aWeSoMe.

I'm getting 600 k/hash highly undervolted.

I will post how to stays in 24h and I will try to get my ASIC quality of the card.

EDIT:
what confuses me is that you dont use the typical:
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1

why?

OK, I didn't saw that last night... strange..
those BIOS specs are for both ?? for supperdupper and Watts optimization? or do you use supperdupper with another BIOS specs.

I understand that.

You don't understand me or I express myself very bad.

What are your BIOS specs?

core clock in BIOS:
memory clock in BIOS:
voltage in BIOS:

Are these the same for the supper dupper power and the max Khash/Watts ratio?

All I need to know now are BIOS specs.

This is my main confusion, specs on post #13 are different from the list you have written. All I would love to know is that:

core clock in BIOS: ?
memory clock in BIOS:
voltage in BIOS: 

gpu-engine in cgminer: 854? or 1025?
gpu-memclock in cgminer: 799? or 1635?
gpu-vddc in cgminer: 0.975? or 1.035?

I understand the fact that 2 cards are not equal and I have to "play" with the cgminers parameters as you said to finally tune the progam.
But first I would like to try to reproduce your results.

To Drakoin:

I'm new to mining, yesterday I installed my XFX R7970 Double dissipation  Model NO: FX-797A-TD Part No: FX-797A-TDFC ver 6.0 to my computer (P6T deluxe OC to 3.82 Ghz). I use a 1000W PSU so no problem here.

I tried to flash the bios with your first values, then I tried your command values. I observed some card crashes and recoveries and card misfunction (lines appearing and disappearing in the monitor).

I returned to 1,175 V bios.  My question is very simple: you are writing about mem clock, voltages etc.. but it is not clear what are the values of the bios, because you can change that values also in the bios and in the command line of the program. could you write down a post with your best bios parameters AND then the best command line paramaters? you can repeat the A, B , C you did, but better explained.

thx (I'm from spain like you )

I'm a newbie. I need to post. I have to write a few lines here first  , OK, stupidity will rule the world !