I wrote to XFX support and they have said to contact Scan regarding the faulty graphics card. Tried it on various systems and OS and it produces similar phenomenon - lines/blocks of colour appearing all over the display rendering desktop unusable.
Whats the procedure for returning this to Scan to get a replacement or different product?
Regards
EDIT: I will place an OLQ RMA request when I get home but how much will it cost me to get it back to Scan?