Computer will not power on..only blinking amber power light,sometimes!!

Hello,
I can't get my computer to power on, yesterday morning the amber light would blink, the cooling fan would turn on for a split second, no diag lights on the back..then after a few tries to power up it came on for about 20sec long enough to see the Dell loading screen then shut off..back to the amber blinking light..then last night wouldn't do anything at all, no amber light.. This morning I pulled out the memory sticks and unplugged the cables from the cd/DVD drives and the harddrive and the card my monitor plugs into..then plugged the power cord in and the lil green light where the power plugs into te motherboard is on and I am getting the blinking amber again..the power light flickers green ten goes to the blinking amber...sorry if this sounds babbly, my iPod is acting as my computer at the moment lol...not sure if I just need to throw in a new power unit or if it would b something else..?
Any help would b greatly appreciated!!

Bump

Have you tried testing the power supply with a paper clip and the case fan plugged in.

I had the same problem and found that I had something plugged in that shouldn't of been plugged in and now my computer works like a charm. Just take your time explaining the problem more clearly.