Sudden Drop in Hash Rate GeForce 650 GPU Card I'm running on a 15" Retina MBP and have just been playing around with mining on it a little bit.  I realize GPU mining is almost dead at the moment, but bear with me.

Overnight last night I was running the BitMinter Java client and getting around ~20Mh/s.  I fired it up again this evening, and for some reason, am now only getting around 5Mh/s.  I'm seeing the same rate on both the BitMinter java client as well as with cgminer.  Nothing has changed on my system over the last day other than having to reboot it a few times for other reasons.  Does anyone have any idea why my Mh/s output rate has fallen so much?
I think I figured out my own issue here.  I reset the SMC on the macbook (http://support.apple.com/kb/HT3964) and my GPU performance is back to normal.