XFX GTX 260 and power supply.

I just ordered a 600W PSU to power a new computer I am building.

Thermaltake Purepower W0121RU 600W ATX12V V2.0 SLI Ready CrossFire Ready Power Supply
http://www.newegg.com/Product/Prod [...] 6817153077

I have a Intel core duo e8400 and a XFX GTX 260 video card.

XFX GX260NADFF GeForce GTX 260 Core 216 896MB 448-bit GDDR3 PCI Express 2.0 x16
http://www.newegg.com/Product/Prod [...] 6814150329

I have been reading that it requires 630W for a non-SLI setup and 36A on a 12V rail. I don't know much about power supplies but I know mine is only 600W and I don't think it has the amps.

After doing a little more research I am fairly convinced that my power supply will not be powerful enough for the video card I ordered. Am I correct? I have been reading other posts on this site that I thought it said the GTX 260 could easily be run on a 500W PSU. So with all of the reading I have been doing I am a little confused.

Thermaltake provides good quality power supplies, that's just not one of the better ones.
With a combined 12v output of only 29 amps it's relatively weak for a 600 watt unit.
Yes, a good quality 500 watt psu can easily power a 260GTX based system, there's one member here running 2 of them on an Antec EA500 to see how much it can take.