I Need Help Asap!

[PCgee]

hello everyone..i'm a new member and i have a serious problem. I was working on a company's computer. i wanted to show them the memory they had in their computers. I unplugged everything from the pc, took out the RAM, showed them, put the RAM back in, and plugged everything back in. I turned on the pc and the monitor and the monitor wasn't getting a signal from the pc. On the screen it said "ATTENTION: not receiving a signal" I've never ran into that problem before. I disconnected the monitor from the pc and reconnected it. I still ran into the same problem. I tried everything to get the monitor to work and it wouldn't.
I disconnected everything from the back of the pc, and reconnected everything. Bad luck...now the pc doesn't turn on. NO POWER! I tried everything again. I can't get the power to come on now. Could i've shorted something out? Everything is connected inside. So...if anyone has any suggestions...let me know ASAP

thanks

[Jiggy]

Hi and welcome to PC Guide,

Whats the pc spec?
1. Make sure all connectors and cards are in firm.
2. Try and boot just with ram, graphics and cpu then power up.
3. Does the PSU fan spin?
4. try these flow charts (http://www.pcguide.com/vb/showthread.php?s=&threadid=24421).(go to bottom link)

[Abbadon]

maybe a long shot but: when you disconected everything for the second time, is it possible you accidently turned of the psu? Often they have a little switch on the back of the case to turn them on/of. If all cables are secure and there is no power, I'd check for that switch. Won't help your screen-problem but at least you'll have power...

[pentachris]

Because the AGP slot sits so far from the edge of the motherboard, it's easy to torque it loose when removing the monitor cable. Make sure the video card is well seated.

You could try disconnecting everything from the back of the computer and try powering up. If it does power up, turn it off and start plugging components back in one by one (you'll prolly want to start with the monitor), trying to power up with each addition. I've seen a computer fail to power up (absolutely nothing happened when the power button was pressed) because of a bent pin on the keyboard plug, and it was that step by step process that led me to the problem.

If that doesn't work, tell us exactly what you mean when you say "no power." Do you hear anything at all when the power button is pressed? Put your head close to the case and make sure you don't hear any fans whirring.

You could try jiggy's suggestion. And yes, when he says just ram, graphics and cpu he means disconnecting the drives and any additional cards.