xfx 6950 1gb problems

Heyup
got my 6950 this morning,
and have started getting weird crashes, its random crash, ive ran furmark and a few benchmarking games and its been fine,
but when im surfing i get a Blue and White Vertical Screen Crash, its all even lines as well (no aritifacts )
the 6950 was a refurbed one from the well known auction site,
its a xfx 6950
i tried unlocking the shaders but mine will not overwrite version 2

If you bought it from ebay as a refurb, it might be worth asking the seller about this. Might have had issues when sold to you. What are you doing when they appear, just browing or watching vids/playing games etc?

Have you tried the latest drivers? They're 12.6, released a few days ago.