Does it beep like it usually did before?
What is this about a video card? If you added an aftermarket card and didn't put in a bigger power supply that is my prime suspect. Use a Volt meter to test it.
Here's a link how.
http://www.techrepublic.com/article/power-supply-troubleshooting-with-a-multimeter/1056686
Bob
Hello, I have a emachine with windows vista, I have keeped it clean and running since i bought it in 2003. My problem is one day my wife told me that she couldnt get the screen to show up, I look at it, and find that my moniter is fine, it shows that its connected but theres no video input. I took a crack at it last night, cleaned the dust out of it( not the 1st time) and I hoped that might have caused the problem, but cleaning it did nothing. I have a aftermarket video card, Geforce. I figured that If i cleared the CMOS it would reset it to the original onboard graphics, but after I atemped that, no cigar. I originaly thought that the A.M. card pooped out but Im not sure anymore. I do not have another video card to test. If theres an idea you may have to, please share. I am currently not at my computer so I dont have the specs off the top of my head but as requested I will get them. Worse Case scenario my motherboard is messed up.

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