I have one about the same. gets ~40 mh on the APU and ~70 on the discrete. It crashes half of the time when you stop mining.
Just a little curious, does it make unbearable noise when you run bitcoin on both?
Are you able to adjust voltage for the discrete?
No it doesn't. The fans runs loud, but no other noises. I haven't tried to raise the voltage but the people on those forums have guides on overclocking and overvolting I think.