Hiya, I'm a bit stuck

I've got a non reference 5850(Sapphire Vapor-X 5850 1gb PCI-E) have also noted some other 5800 series cards have the same problem as me

Everything works perfectly on my system except the gfx, when I load up and its on the screen before the login, its black with green, blue and red dots splattering across the entire screen(many thousands of dots) then the desktop loads, and sometimes looks normal, and sometimes looks corrupt as hell.

when I load safari sometimes Its corrupt in the way of sections of it show images from before(like its taken a chunk out of the video ram from earilyer) I had a webpage open(my own webpage) and was trying different tweaks to get it working and checking safari now and then, then when i loaded safari again In the top right corner I saw a garbled corrupt picture of my website for a split second before it changed to something else, then dissapeared.

also certain letters and text are different/missing entirely in safari(safari isnt the only part that has this problem, theres gfx corruption in almost everything.

Things I've tried:

Gfx enabler off and on(with every framebuffer that is in there, both with it on and off)

Use ATIRom

SMC fake ping thing I saw somewhere on some forums

set all my cards clocks in its bios to 725/1050(default 3d setting) even under the low power settings that used to be 157/300

reflashed my card with a reference bios off a gigabyte, Asus, XFX, and the non reference card variants of these brands

tried an older kernel

also tried 10.7.5 but couldn't get it to boot the installer due to the ACPI problem that requires a kext change to an older kext, but cant load the kext into the installer disk

searched all over the place, only found three posts, 2 that went off topic with no solution, and one where the guy got someone replying but then didnt reply back to the guy replying so it also wasn't solved.

Apparently this is some sort of bug with the kernel, from what I can see tho its related to the video ram, as its showing me momentary pictures of stuff I've done before

other than that the acceleration works, dvd player test works (with no corruption in the player window itself, but things get corrupted looking all over the show.

also things like the screensaver work without corruption, its odd.

Anyone who could help it'd be greatly appreciated, as I want to see what this FCP is all about that everyone keeps telling me is awesome, and worth spending 3k on a new mac for, I'd like to at least try it before I decide to splash out on a real stable mac.