Power Issue. help!

[ClintEastwood]

recently my computer stopped powering up, and i'm unclear as to why. i'll hit my power but and my caselights power up for maybe 1.5 seconds. i switched the power supplies thinking that was the issue. i'm thinking it might be the motherboard now. can anyone give me another possible diagnosis before i resort to finding a new motherboard?

 

[linkin]

Are the motherboard standoffs in properly?

Try unplugging all unnecessary hardware. Unplug your dvd drive, use onboard graphics, one stick of ram, one hdd and no other add in cards. If it boots, add the other stick of ram. if it works then keep adding hardware until something causes it to stop booting.