Inspiron 7559 Gaming starts inconsistantly; blank screen, no fans, keyboard and power lights on
My Inspiron i7559-763BLK Gaming laptop has started experiencing an issue where it will inconsistently power on. I can press the power button and get lights, but no activity indicating anything is going on. Keyboard and power lights turn on, but that aside, there is no indication that anything is happening with the computer. No image comes on screen either. I recently took the screen out to reset the connection between the screen and cable, to attempt to fix an occasional screen flicker, but I doubt that this is causing it as I am pretty sure I reinstalled the screen correctly when I tested it (it worked).
I also reinstalled the Intel graphics drivers recently to fix a driver related BSOD issue, but I don't think that has anything to do with it either. Basically its just: power button gets pressed, lights come on on keyboard and power button, fans and screen are generally unresponsive. Sometimes it goes on without a problem, but recently there have been issues with getting the thing to start.
I haven't tried anything yet, but I've heard of trying a hard reset (battery removal, drain residual power), and reseating the memory. Anything else to try?
Update: After a couple more tries, the PC boots up, but lt's still inconsistent. It seems to be fine sometimes, but not fine on other times.