PowerMac G5 wont boot, help???

1.6 ghz 4gigs ram 3rd party power cable, new psu could be bad... no hdd. When i press the button on the front, the blue led comes on only as long as i press the power button.

Check out my youtube video that full shows the problem:

http://www.youtube.com/watch?v=Y8BtzEDreV8

What may still me salvagable on the Mac, or is it repairable and if so, what is needed to repair it?

Thanks for any help, feel free to ask any questions, ill get back to you ASAP.