I think you would be fine but I would try to avoid long hours of high load. Check out this 7850 http://amzn.to/14LXrV1 it's a great deal right now.
By high load you mean gaming on high graphics for much hours ? Thanks for the link
Yea, running your GPU at full load being 80-90% or more for hours at a time. You'd probably be fine doing so but you may want to take breaks. Download MSI Afterburner to monitor your GPU and you're welcome for the link. =)