I'm working on a 5 or 6 year old pc. It was brought to me with the psu pulled out and half the wires unplugged. It has 2800+ athlon, a built in nvidia card, not much ram, and its a hp pavillion. Not sure if any of that is relevant, but problem is, I installed a new psu, and plugged all the wires in. I turn the pc on and fans run, drives runs, hdd sounds like it runs but nothing comes up on the monitor. I tried coming off the back of pc and the video card, nothing. I took the video card out and still nothing. I double checked the wires and there good. From what I have read, its probably the motherboard. Thing is, the pc was a hand me down twice over. So noone seems to know when the last time it worked. At some point somebody got a new psu for it, probably not knowing if the other psu was bad. So maybe something happened when it was moved from one place to the next. I just don't know much about troubleshooting faulty hardware. Any help would be appreciated. Thank you.