Power supply help

Hello everyone,
I'm soon upgrading my pc from gt 330 to 6970. my question is about power supply I'm certain that mines isnt powerful enough but I would like some help explaining the PSU itself my current one is.

AC [ 100-127/220-240w, 10/5A, 50/60hz ]
DC [3.3v| 5v |12v1|12v2|5vsb|-12v]
DC [16A |20A| 18A | 18A|2.5A|0.5A]
MAX [ 450W ]
Peak[ 500W ]

Can anyone explain this information so in future I can easily read what I need from a power supply as I know that W's isnt everything, it's also got something to do with 12v rails and Amps

Its best just to ignore peak... base your calculations on Max.

http://www.amd.com/us/products/des [...] iew.aspx#3

states :

550 Watt or greater power supply with one 150W 8-pin PCI Express® power connector and one 75W 6-pin PCI Express® power connector recommended

Which is 150w/12 12.5a (free) on the rail connecting the 8-pin, and
6.25 a (free) on the rail connecting the 6-pin.

We will need the make/model before proceeding with a recommendation, but preliminarily you look clear.

For your first step in sizing the PSU, I would use a PSU calculator like this one:
http://www.thermaltake.outervision.com/
Just enter the values as they pertain to your build. There's a spot there for you to enter the graphics card you want to use, among other variables...

Then head over to Newegg and look up PSUs. Sort them in order of Best Ratings. That will give you an idea of the best brands. Then if you want an expert's opinion, head on over to Johnny Guru's site and check it out...
http://www.jonnyguru.com/modules.p [...] ecatnum=13