PC won't turn on, have changed MB, CPU, and PSU

Hello Everyone. This is my first time posting here and I need some help. I have a custom built PC which I constructed in 2006. I have had problems in the past with Power supplys going out on me (I buy the cheap ones lol). This morning I woke up to my computer turned off (usually its on). When I pushed the button to power on, the LED lights of my case blinked for 1 sec and then nothing happened. I though oh crap my power supply again. I went and bought a 575 power supply and still it didnt work, same thing blink for one sec then nothing. I was running with an Abit IP35-E Motherboard with a 2.6 ghz core 2 duo (like i said its been working for a few years). I then decided it had to be my motherboard and processor so I went and bought a new one. I am now running a Gigabyte GA-EP43-US3L motherboard with an Intel 2.9 ghz core 2 duo. I wasnt looking for an upgrade just a fix for my PC. Well I installed the motherboard and chip..plugged everything in and once again the light blinks and then nothing. I have all this in the case I posted the link for below. Could it be my case? Can someone please help. Fortunately I have a backup computer which I am using now but it sucksssss. I have exhausted all my ideas other than its my case. My theory is that even though I got my new motherboard, processor, and power supply...if the stupid button on my case has shorted out or something then the other components cant recieve the signal to turn on. I need someone smart on this one...thanks in advance...and if u fix this problem I will paypal u 2 dollars..lol ha..

This is a link to the case I have...
apevia.com/images/products/X-DISCOVERY-AL-1_500.jpg
 
...if the stupid button on my case has shorted out or something then the other components cant recieve the signal to turn on.
If your case has a reset button, it will work the same as the power on button. Connect the cable from the reset button to the power header pins on the motherboard. Whether it works or not will help narrow down the problem area.
 
A simple test is to disconnect both the power and reset buttons and try starting the system with a long screwdriver across the pins where the power button cable goes.
If either of these two buttons has got stuck it will have the same effect.
 
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