
WORKED LIKE A CHARM!!!!!

Reference MSI 7970 OC edition (1050mhz clock) 2PMD3GD5 boots with full bootscreens, reporting correctly (having used hexfiend to change 7950 to 7970 as per SamPotts suggestion), the works.
I am indescribably happy with this, thank you so much to Netkas and Rominator for this fix, and also to SamPotts and smjones for your feedback and assistance that made sure I didn't screw it up!
I followed the instructions very carefully and it went perfectly. The only thing I NEARLY screwed up which I didn't see anywhere in this thread, that the veterans know but a relative newbie such as myself might have missed is that the 7970 has a dual BIOS dip switch, which MUST BE IN POSITION 1 for this to work. My card arrived with it in position 2 (locked factory rom) and at first I dumped that ROM, so had to re-dump the rom after switching to BIOS 1 before patching/flashing.
I am a very happy samurai.
Pic related
Guys, I've had some bad luck and I'm looking for a little advice

As of about 5 days ago, my 7970 which has been sitting happily in my 2,1 since January seems to be borked.
My mac just decided to reboot one day and when the card tries to boot on the 2,1 I get lots of staggered horizontal lines in vertical columns and it doesn't boot.
I took the thing apart and re-applied some arctic silver to the GPU and the colour of the lines changed but they're in the same pattern.

I can still see the apple logo from the EFI while it's booting, and here's the interesting thing:
I threw it in a friends old 4,1 that I'm borrowing (8 core 2.26, 16GB Ram) along with an old drive I had with an install of 10.7.5 and I get EXACTLY the same symptoms, but interestingly
I can boot through to the OS fine and the thing still posts as a 7970 fine in 'About This Mac'. It seems to work fine, except for the fact that it's almost completely useless!
I thought about oven re-flowing it but from doing a little reading it looks like it might be the VRAM, and the fact that it boots into ML makes me wonder if sticking it in the oven is a bad idea.
I'm currently trying to boot into bootcamp to see if I can underclock the thing, but for some reason my bootcamp drive doesn't seem to be bootable in the new machine :/
And lets say in dreamland I manage to get into MSI afterburner and turn things down and that does away with my evil lines, will I need to re-flash for the new clock speeds to stick when I'm in OSX?
Do any of you guys have any idea if I can save my beloved 7970? I was so happy with it !
Halp plox X