I have a Dell Studio 540 that I purchased by in 2009, recently it has been having problems waking up from sleep mode. When it is put to sleep, and left that way for maybe 2-3 hours, when you wake it up, the fans start and the light stops blinking as if it is starting up, but the screen never turns on. I am forced to turn it off with the power button and then start it up again. Because of this, we cannot put it into sleep mode because they we have to "wake it up", shut it off, and turn it on again. Now, I thought it might be the GPU, so I swapped it out for another, and I still have the same issue. So I put the original GPU in there and now I'm stuck. I don't know where to go from here and I'd really appreciate some input, thanks!