New x1900xt -> PC wont boot, PSU?

Hi guys, I am almost sure this is problem is because my PSU is not powerful enough. But I wanted to get some input.

I have a ASUS P5AD2 mobo, 3.2GHz intel presccott HT, 1GB ram, 1 SATA HD 1 IDE HD 1 DVDRW 1 CDRW.

As you can see its a pretty loaded system. I have a 480w PSU.

I just got my x1900xt today and I install it and I go to turn on the computer and the thing wont start. I read the requirements and it says at least a 450w PSU so I thought I was ok. I had to buy the adapter for the video card because I did not have a native 6pin PCI-Express power connecter in my PSU.

The PSU is a little older too and only had a 20pin ATX connector. When I upgraded my PC i had to buy a 20 -> 24 pin adapter to get it to work with the P5AD2.
The brand is antec true blue. I am pretty sure this is it.
http://www.devhardware.com/c/a/Pow [...] -480W-PSU/

I think it is the PSU because when I go to turn it on, the CPU heatsink fan twitches but the thing just wont turn over and boot. I think its just too much for the PSU to handle. Ive tried unplugging everything except the harddrive I need to boot, the graphics card, and the mobo, (the bare essentials) and still have not had any luck to get the thing to start.

If i disconnect the PCI-E adapter that I bought (that converts the 2 x 4pin molexs into the 1 6pin connecter) and leave the vid card in the slot, the system does turn over. I didnt leave it on long enough to see if it POSTs, but it gets further than dead

I am impatient and have already ordered an OCZ power supply 700w that has the native 24pin ATX and the 6pin PCI-E.
OCZ psu: http://www.newegg.com/Product/Prod [...] 6817341002

Ive been doing some reading and it looks like the card requires a 12v30A rail? Isnt this alot? I got this from a Power Color spec here:
http://www.excaliberpc.com/PowerCo [...] 64195.html

I didnt see anything that matched this 12v/30A on the PSU that I ordered. Is the OCZ 700w gonna power it and all of my peripherals?

I wanted to see if you guys thought that I have made the right decisions. That PSU was pretty damned expensive

Thanks for all your help! It is greatly appreciated.

yeah u cant add them but the OCZ will run your system easily.

but...

http://www.newegg.com/Product/Prod [...] 6817103930



that shoudl easily run ur system and u supposedly have that....hmm

What was your previous GPU? Are you OCing? IMO, your orig PSU should have been able to power your rig. Are you sure that all of the power cables are seated properly? The video card is seated properly? Try booting with minimal hardware and then adding components one at a time. Monitor voltages after every successful boot and then let us know what your readings/results are.

The PSU you've ordered will definitely power your rig - it should power two rigs with those specs...

Guess it depends on the rig... my old 600w enermax couldn't power my one rig....