Recently I installed a new power supply, video card (Galaxy Geforce 9500 GT 1GB), and harddrive in my desktop computer (HP m8210n).
The problem is, after about 20 minutes of being "on", my computer monitor goes into sleep mode, and will not come out. The computer "brain" continues to run without issues, but there is no display. I replaced my power supply because i thought it was an issue with my new graphics card requiring more voltage, but the problem persists. I've read about other people having similar issues, but i've never seen a clear answer given. Any thoughts?