I was using my PC for hrs today with hw and web-browsing then went to store, PC fell asleep and now GPU won't give signal, PC powers on and the MOBO shows the all okay code. but won't display on either monitor, so I changed the output to the mobo and now it works.. but still not when monitors are plugged into GPU, why could this be? was working fine for years and then all of a sudden no. GPU is liquid cooled so I don't know if it is even on. Anything I should try? Precision X does not detect the GPU.