Hey guys im extremely aggrivated by stupid computers. I built my moms computer about a years back which has a asus A7N8X-X mobo, 512 ram, and 2400XP amd. Her case was really ghetto and we decided to upgrade this week. I went to the local computer store and bought an OKAY case. It came witha 450W new PS which was an upgrade from the old case. I transfered the mobo, drives, and Hard disk, screwed them all in. I plugged in my IDE's and power cords. Then looked in the manual to refresh my mind where the power SW pin/cord goes and i plugged it in correctly. I go to check if the machine works and theres not a sound of electricity in the hole machine. NOTHING.. :( Im not sure what the heck is going on with this thing. I tried reversiving the pin to see if the grnd was backwards or something but still nothing. I even ripped the old power sw cord out of the old case and plugged her in, and still nothing. If anyone has suggestions to try please feel free. Thanks

Check for shorts to the new case. I know this sounds stupid, but ensure the switch on the back of the PSU is in the on position and the setting is for proper voltage to your area (115 or 220). We can fix this, but you're gonna need a butter knife, a roll of duct tape, and a car battery

I'd say the motherboard is shorting out on the case. Did you use the brass or nylon standoffs between the motherboard and the case? If so, did you only use the standoffs where there are holes in the board for them? Double check all the connections to the board, did you plug in the 4 pin power plug?

yes yes its 115 :P im not sure what you mean by brass or nylon standoffs. I am asuming that its what is holding the mobo. In the old case i can see there is some metal elavating it and in the new one there is not. As well. Here is the good news. I took everything out and plugged it all back into the old case and she workds fine and dandy. **phew** thought i blew a mobo :D It must be either the new power supply is broken or not compatible. Ne suggestions? i am going to switch the old ps to the new one.

Check the PS first. do this by following this link... http://computing.net/hardware/wwwboard/forum/33955.html that will make sure PS works at least. then goto MOBO checks suggested earlier.

"In the old case i can see there is some metal elavating it and in the new one there is not" Does this mean you screwed the motherboard directly to the case without installing standoffs? If this is the case, you would certainly have shorting problems!

i tahnkk all of your for yout time and advice, the case was shorting the mobo and as soon as i screwed in the brass stand offs she worked. Thanks a bunch.