I use two monitors with my pc, but they won't come on during startup. I assumed my powersupply was going down since the computer would randomly shut off and wouldn't turn off by pressing the button. Yes, it would turn off if I went to start, etc. I did clean all the dust inside the machine, fans, etc. (a routine clean). I bought a new power supply, but I still have the same problem--the monitors won't come on, but they work fine on another computer. I'm puzzled to what is wrong with the computer. Could it be the video card?