If you suspect video card on its way out, to prove it, remove the card to test the pc by integrated video. If POST is normal, you can then narrow the suspect to video card.  If video issue persists, first replace cmos battery with a new battery and clear cmos settings via motherboard cmos clr jumper.
A great computer - couldn't wish for better.  Suddenly - no video on switch-on.  Video board is GTX 1060After a while, the monitor flicks to the monitor logo - regular on/off flashing.  I can hear, but not see,  the POST running up (clicks and hard drive noises) and the num-lock and mouse come live.  Still no picture beyond the flashing monitor logo.Turn on/off a few times and flashing logo gets slightly longer and brighter until it suddenly becomes normal,  the Dell start-up comes on and the computer works perfectly for the rest of the day.   No access to the BIOS via f2, but I wouldn't see it anyway.Probably a dying GTX 1060, but would appreciate any help, please.  Drivers are up-to-date according to AVG.
XPS 8930, intermittent video