I am hoping someone could help me out on my power up problem on X51.

After I pressed the power button, the tower now takes 2 go to turn on (Lights on > off > lights on again) and 50% of the time my screen remains in black (no signal).

To overcome the black screen problem at the moment by I have to keep restarting manually until I am in luck then everything just works as normal. It is a bit frustrating as sometime it takes many times before the unit eventually boot up.

I ran the dell system test and it is telling the unit is in good health. O.o

Can someone point me in the direction on whether this is a hardware or software problem and solution if possible?

Many thanks