Hey I been having some problems with artifacts in games. Sometimes textures flicker. Artifacts of various shapes and sizes show up usually after a couple games of dota 2. I built my computer almost exactly one month ago and it has been doing this pretty much from the start except before the artifacts I believe just flashed on screen fast enough to where I couldn't tell what it was but I still noticed. In dota I've seen green triangular artifacts among other things. I've tried running Furmark for a while but even though it pushes the gpu much harder than dota 2, there are still no artifacts. It maxes in furmark at about 60C and running every game I've tried on it at 40C. CPU and system temp don't usually get higher than 40C either. These are my system specs:

Gigabyte Z68 Intel Motherboard

16 GB Gskill Ripjaws SDRAM DDR3

Sapphire Radeon HD 7770 GHz edition

Intel Core i5-2500k (with built in gpu)

Corsair 750 Watt PSU

windows 7-64 bit

I have the latest drivers for everything. What should I do about this? Try to RMA my graphics card? Are there other things that could be causing this?