If it doesn't even show the BIOS startup screen, and doesn't go into the BIOS setup if you press that key (F2 or Del or F10 or escape or whatever it is on your motherboard), it's either the PSU, the motherboard, the RAM or the CPU or the graphics (either the integrated or the separate card, whatever you connect the monitor to).
So you start replacing parts until it works in a cardboard test.
Hey all, as you can read the title i'm having a comp issue here. It powers up, fans spinning but that's about it.. screen stays black nothing boots. ( Screen works 100 % tried it on my PS3 and also tried th pc on an other screen , it doesnt boot either). What I have done so far: I have tested the PSU with a paperclip, it works. I have taken out the ram, cleaned it with an erazer. I have taken out both of my ram sticks and my motherboard keeps beeping so I'm assuming my mobo is not dead. I have pulled out the CPU fan and powered up to see if my cpu heats up, it does, so I guess it works ? I have taken out my nvidia gtx card, still same result it doesnt start.. als unplugged my hard disk and dvd disks.. still nothing. I have removed my CMOS battery and put it back in with, however I havent tried out a new one yet. What should I do if a new CMOS battery does not work ? Did I miss something ? pleas help ..

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