The r9 290 and 280x have been said to have artifacts, flickering or high temps(especially 290 going to 95c). I really need help if I am to get one of the two, and any fixes that might be known for getting rid of artifacts and to keep the GPU cool.
Only times I've heard of artifacts was due to either not having a proper PSU or an overheating issue, the reference cooler certainly is not enough in R9 290/ 290x, however most card manufacturers have been using better cooler designs to solve this issue, like the Sapphire Vapor-X version, you'll see their R9 290x doesn't go beyond 70ºC:
Only times I've heard of artifacts was due to either not having a proper PSU or an overheating issue, the reference cooler certainly is not enough in R9 290/ 290x, however most card manufacturers have been using better cooler designs to solve this issue, like the Sapphire Vapor-X version, you'll see their R9 290x doesn't go beyond 70ºC: