Weird graphic issue?

[driveandkill]

Hey guys!
I recently installed Amnesia on my new pc to get some awesome custom stories.
When I started it I was wondering why the blood in the main menu looked like squares. When I played for a while I saw that tissue and other objects have a weird bug. They have some white boxes around them. This bug didnt appear on my old PC which had a 5770, and a processor from AMD.
Specs of my new pc:
Windows 7 home premium 64 bit
AMD 7970 reference
Intel core I7 2600 (not K)
16gb ram
Game installed on a 500gb HDD from WD (same HDD as in my old pc)
AMD Catalyst version 12.3

Attemps to fix: game veryified on steam, googled the issue without success

screenshots: picture 1 = white boxes picture 2 = main menu blocky blood
http://steamcommunity.com/id/driveandkil...290879565/?
http://steamcommunity.com/id/driveandkil...290885068/?