See my post
https://bitcointalk.org/index.php?topic=79889.0Basically, use AB, set the voltage in cgminer and ignore what cgminer reports. Use GPU-Z sensors' page along with killawatt to verify your undervolting.
You can undervolt 7970 and run cgminer with it. Just lower voltage slowly until you get to the point where AMD driver crashes too frequently.
Then increase the voltage back a bit until you reach a "stable" setting.
That's more or less what I have been testing over the last couple days before I switch over to permanent rig setups with my 7970's.
I ended up going back to Afterburner as well (as suggested by a few people now) and it seems to be working quite well.
I was really hoping that things would have been '
HD5xxx-Friendly' using CGMiner, but alas, Afterburner (
for VDDC control) to the rescue.
I still can't get over the gains in power savings achieved by a small undervolt, yet still a small overclock. I won't lie, I was hoping for HUGE mh/s performance, but in the end, I am happy that it at least all runs smooth...FINALLY....lol
Thanks to everyone who helped during this difficult time...lol
bitlane
<EDIT>I should also add that I was surprised to find (
perhaps only applies to my setup) that stability in Windows while mining and attempting to run memory clocks too far under 900Mhz was nearly non-existent at times, while trying to cut voltage....regardless of the voltage setting(s).
For now, I have settled on using 900Mhz as my memory clocks across the boards. Again, this is using all Gigabyte Reference Cards (YMMV).
Going back to an RC/Beta Driver (thanks jim) has also given me the ability to run 5 card rigs (and have them actually boot), so I am pleased with that as well.
I was starting to loose faith in CAT 12.3....lol. The driver package I am using actually reports as being CAT 11.12 (again, perhaps not and simply a 11.12-based beta/release candidate).