Power supply issues, please help

I believe my power supply is going bad, and before purchasing a new one, I'd like some help. I am not too savvy with PSUs.

Here are my system compentents:

Intel Core 2 Duo E8500 Wolfdale w/ Artic Cooling Freezer 7
ASUS P5Q SE/R LGA 775 Intel P45 ATX
4G Corsair 240 Pin DDR2 SDRAM DR2 800 (PC2 6400)
ASUS EN9800GT Ultimate 512M Geforce PCI Express 2.0 x16
OS: Windows Vista 64bit Ultimate

I was putting my computer to sleep, and when I tried to awake it, nothing happened.

When I try to start it, everything powers on for about 4-5 seconds, then turns off for about 5 seconds, then turns back on, all fans spinning, DVD ROM works, everything is working, but no picture on the screen.

I tried to unplug the harddrives to get to the bios, but the PC won't post to the BIOS.

I think its the power supply? If so, can you reccommend a good one for my system off of newegg?

Thanks in advance, I REALLY need help on this one.

No there is nothing, which makes me think power supply. Beeps usually mean hardware right?

So does it sound like the power supply to you as well?

Yeah it worked perfectly, its only about a month old, never had any issues. my only guess is i should have upgraded the powersupply when i updated all of these parts.