I normally hibernate my PC when I'm not using it instead of turning it off. A few nights ago I went to use my PC and when I took it out of hibernation, there was no video and the blue power button on my monitor was blinking instead of being solid blue. I messed around taking out RAM, video cards, CMOS battery and reseating everything in different places but nothing seemed to work.
I thought it was the monitor because I'd read about Samsung monitors' capacitors blowing, so I ordered a new one and it just arrived today, but it will not output video to the new monitor still. I've plugged the DVI cable into both of my GTX 280's and no video, I've plugged VGA into my mobo and no video and I've plugged an HDMI into my mobo and still no video.
I currently have my laptop hooked up to the new monitor with a VGA cable, so the monitor does work.
My computer turns on just like it normally has for the past year, all the lights come on, fans hum up, I've checked and the CPU fan turns on as well.
If no beeps and the speaker is correctly connected, then it could be a motherboard, a CPU or a power supply problem. You can try testing the power supply in a different computer. Are they under warranty?