So a few weeks ago i bought the antminer U3 from ebay, but when i got it the wall to adapter cable wasn't in the package and since i'd blown $60 on this i couldnt buy a new one yet  just today i bought the cord, went home and got it working   when i went to slush's pool it showed after 5-10 minutes that i was at 42 GH/s   But it slowly started to go down  currently it is at 25 gh/s and i want to know why, is it because its hot, or is it something else, please help me i want to get my full 60GH/s worth while keeping it cool