R9 280x Artifacts problems, tried everything, help?

I bought an MSI R9 280x 3G from Overclockers UK a month ago, after installing the card it gave me artifacting and random crashes while playing games such as Guild Wars 2, League of Legends, and Hitman: Absolution. I sent it for an RMA to Overclockers and they said: "no fault found, perfomed fine on benchmark/stress tests for 24 hours", they gave me advice such as reinstalling windows and downloading the latest directx runtime from Microsoft. So I got the card back and yeah... I was still receiving artifacts while playing Guild Wars 2 and one crash from the Titanfall Beta which had gave me a frozen screen with artifacting and reset my computer.

I have a video of the artifacting happening in Guild Wars 2 if anyone is interested. http://www.youtube.com/watch?v=DzpjO5d4izI

I have also installed MSI Live Update 5 to install any of the latest utilities and drivers from MSI.

Overclockers say that they tested it for 24 hours on benchmark software, Battlefield 4 and the other latest games, they also seem to not care about my having problems on Guild Wars 2 and League of Legends because they are either old or do not run on an intensive engine such as Frostbite from BF.

Any help?

dude... don't bother with MSI crap. get the 13.12 catalyst drivers straight from AMD.