The flash instructions are over on the Netkas forum.
THIS is the thread you will need.
Some folks have posted EFI-ready ROMs for some of the more popular 7950 card types in the shops and if you match the card exactly, you can just drop the ROM straight in. For example, I am using
THIS card, manufacturer code 11196-17-40G. If you were to get the same card I could send you the EFI ROM and a backup of the original ROM. PM me if you do end up with that card.
I should add that it is possible to mess up the flashing as pjcltd found recently. You really do need to pay attention to the guide to guarantee success and you can also end up with a faulty card out of the box.
The latest copy of ATI WinFlash is all you need if you are sent an EFI ROM. You can get ATI WinFlash from
http://www.techpowerup.com/downloads/2232/ati-winflash-2-3-0/ and there is a guide at
http://www.overclock.net/t/1353325/tutorial-atiwinflash-how-to-flash-the-bios-of-your-ati-cards