And replacing what's failed. Since you are into PC repair I'll not duplicate the checks for connections, the resets and such.
This appears to be a 2009 model http://reviews.cnet.com/desktops/dell-inspiron-545s/4505-3118_7-33703096.html so did you try the usual disassembly, cleaning and such?
Bob
My moms god son has been using my computer but several minutes ago he called me in and my screen is black http://www.youtube.com/watch?v=gPyIc3pkIys how can i fix this?

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