Motherboard getting power but wont boot? wt?

OK, i bought some new parts for my computer(psu,mobo,proc,vid card)
and everything works fine! yay!

now where the problems start,
i wanted to move my old psu,mobo,proc,vid card to my moms computer-
well i bought a new case for it and put everything in

turn the psu on, everything looks good- mobo LED goes on, and the ethernet LED goes on-

i press the power button- NOTHING HAPPENS



===what ive tested===
i tried a new psu that works - that apparently isnt the problem | same result
i tried a new power button that works | same result

im going to take everything out of the case and try to run it stand alone


---
i guess my question (besides wtf) is could i have blown something in the mobo, but it can still get power

ive never had this problem (built probably 6 computers atm) and am lost


ANY SUGGESTIONS? (or tests i can do)

 

Your motherboard might be shorting against the case; make sure its all secured properly.

 

Check and recheck all power connections and LED's, especially mobo power and the PSW and PWR LED's. LED's only work one way around, so switch them around if you have to. And lastly, consult the manual if necessary.

 

Double-check the case-front plugs - ATX PWR, especially.

I just put my comp back together (had a FUBAR'd mobo that I RMA'd) and stuck the ATX PWR plug onto the wrong set of pins. The ready LED on the board lit up, but nada when I hit the switch. Moving the ATX PWR plug one pin over got that set right...

 

Probably dead mobo by the sounds of it

Clear cmos.

Use the bare minimum of hardware: basically just use video card, hard drive with os and 1 stick of ram. Also just use the power and reset button, dont bother with led's etc.

Try your ram, cpu and gfx in a working pc, try working stuff in the non working pc (use the better psu as the old one may have killed your mobo).

If that dont work its dead, might wanna ditch your old psu if is cheap n old, not worth saving a few £ only to kill any new kit. Maybe get a surge protector too, dunno how well they work but they must help?

Do all the stuff in small stages as if it does work but you do it all in one go you wont find the faulty part.

Good luck

 

Do any of the fans turn for a split second and then stop?
if not flip the power switch connector on the mobo upside down.

 

I had a case once where the power switch was connected wrong (power switch cap on the reset switch), the most fail safe way to check it is to unplug all the LEDs and switches, and just short the 2 power pins out with something metal, a knife or a screwdriver etc.