I've got a friend's HP Pavilion DV4 laptop he needs fixing, and I am looking for some help on figuring out what the possible problems could be that are leading to these problems.
When I start the computer, it goes to a blank screen randomly. Rarely does it ever make it to the desktop screen; usually blanks out during the "Starting Windows" screen, although it also blanks out right after I turn it on, and everywhere in between.
It's not the LCD screen giving out; I've tested that thoroughly. It is also not a overheating issue, as I have already cleaned out all the dust in the fans/heatsinks. Furthermore, at times when I WAS able to get to the desktop (and for some odd miraculous reason it did not crash for hours), I did 30 minute long CPU and GFX stress tests, to which the computer DID NOT crash..
So what exactly are my possibilities? I am thinking it is either the power supply, the hard drive, or the memory. There are two sticks of RAM in the computer; I took one out, booted it and ended up with the same problem. I switched the one stick with the other and got the same results. I also tried running memtest, but halfway through the test the computer would go to the blank screen.
What are your thoughts/opinions? Thanks in advance.