I have a Dell XPS 8300 that randomly goes into power saving mode. It could be anywhere between 1 to 5 minutes before it does this. I know the monitor is working as well as the cable, so neither of those are the problem. I actually already paid Dell to fix the issue, which they did, but now it's back to the same problem I was having before, and they want me to pay again. I am wondering if I need a new graphics card. If anyone could help me with suggestions, I would greatly appreciate it.
A quick test of the added discrete video card would be to power the XPS 8300 off. Disconnect the power cable from the XPS 8300. Lay it down and open the cover. Disconnect the monitor from the video card. Remove the video card. Connect the monitor to the onboard video HDMI out port or the onboard video VGA out port. Turn the monitor on, then the XPS 8300. If it stays on using the onboard Intel video, then the video card may be faulty.