Today I came across a Dell GX520 that is in small factor form (SFF) that would turn right away once you tried to turn it on. It gave no error code or beeps. It would just turn off and if you tried to turn it back on it would do the same thing.
So I started to disable the connections to the cd-rom and floppy drives and still nothing. I finally removed both sticks of RAM and now the computer would beep but not turn off. Now that I know the computer is able to stay on and not shut off right away I knew that the motherboard and power supply had to be ok…it had to be the memory I just removed.
I put one of the memory sticks back into dimm slot 1 and turned it on. It turned off right away again. I then took it out and put the other memory chip in. This time it turned on and stayed on and finally booted into windows. YAH!
One of the memory sticks had gone bad and this was causing the computer to shut down right away. So if you come across this type of problem with any type of computer try removing the memory and installing one by one to find out if you have a bad memory chip.
till next time,