this is a long question so here it goes. My mom went away for a week and when she came home her computer was on and she had turned it off before she left. She couldn't get anything on her monitor, She tried to turn it off with the power button on the front and nothing so she had to unplug it. The computer was still under waranty so she tried to unhook it but didn't know that she had to unscrew her monitor cable and ended up ripping it out which voided her waranty. They (Geek Squad) said they wanted $300 for a new motherboard. I said I could do it for her cheaper. I replaced the motherboard hooked everything up and plugged it in and it powered up on its own I hooked up to my monitor and it said there was no signal. It wouldn't power down when I tried the button on the front. The cd-rom wouldn't even open, until I unplugged the computer and the unplugged all drives from the motherboard then it would open. when I had everything unhooked I hooked up my monitor again and plugged in the computer still nothing came up on the monitor. shouldn't I get a set up screen with which processor and what motherboard is in it? Is the chip fried? oh ya it was an emachines T 2865 with an athlon XP 2800+, 512 ram, 160 g HD. And I replaced the board with an Asus A7V400-MX. Please help me!!

Just a quick reply from a quick glance I see that new mobo:

http://dlsvr03.asus.com/pub/ASUS/mb/..._a7v400-mx.pdf

Has a CPU spec of:

Socket A for AMD Athlon™XP with speeds up to 2.25+ GHz Thoroughbred/Barton core support

Where you are using athlon XP 2800+

Do you get any beeps?

The athlon 2800+ is a barton core and I moved it from the old emachines board to the new asus board and I don't get any beeps. I don't even hear the HD boot up at all, just the cpu fan thats it

What I was wondering is the Asus board only supports a CPU with speeds up to 2.25+ GHz

Where you are trying to use a 2800+

the 2800+ only has 2.09ghz when set to factory specs and not overclocked. Its my moms computer it doesn't need to be overclocked. Well 2.083GHz if you want to be techincal.

OK sorry. I was confusing my #'s

Anyway besides appearing like the power switch may be bad (always on) that still doesn't explain the total failure.

Are you getting any beeps?

I would try with just RAM & CPU. I see that that board has onboard VGA.

I tried just the monitor,MB, cpu, and ram and nothing came up on the screen I even used a seperate power supply. I am stumped unless the board was d.o.a. and I'm not getting any beeps

Try without the RAM to see if it beeps. Otherwise:

The only other thing that I can think of is to test the CPU.

Either try the existing one in another machine or try a new one in this.

I put the cpu in my girlfriends computer and it worked fine

So the CPU is good! Does it beep if you boot without RAM? There is a power light on the board: is it on?