Upgrading GPU - new PSU needed?

Hey guys - I've decided finally retiring my MSI 560Ti 2GB OC edition and going for either the new 290X or a GTX 780. I'm waiting Mantle to be launched and thoroughly tested before I make my final decision..

But will I need to upgrade my PSU? I'm running a Corsair TX650W with an 80+ Bronze rating, and I know for a fact that it lacks the proper pin connectors to support either the 290X or the GTX 780.

On top of that I'm not sure if 650Watt is even enough for my build by then.

I've tried using different calculators online, but they tend to recommend everything from 450Watts up to 750Watts...

Help? :)

I don't do any editing or other special stuff, mostly just school work and gaming!

My rig:

Sabertooth 990FX

AMD FX-8350 @ 4.6Ghz & 1.44V at full load, stock TDP 125W

2x4GB G.Skill Sniper @ 2006Mhz & 1.52V

Corsair H80i CPU cooler

2 SSDs & 1 HDD


Btw,  I just joined your community - and I must say I am extremely pleased to be here! I've downloaded and converted all your INBOX.exe videos (Burned through those in 3 days) and The Tek (Still going) and put them unto my iPod... Apple, I know :( I sure hope that's not breaking the "Terms of use" or anything 

 - Thomas from Denmark

For a single GPU 650W bronze is enough and still have headroom left to overclock cpu and gpu. If your PSU doesn't have enough pinouts just use the molex connectors. 

650 w is more than enough to run that rig with either a 780 or a 290x. Both cards require one 6 pin and one 8 pin power cable to run, if you only have 6 pin connectors its fine, I'm pretty sure the cards will come with a molex to 8 pin or something like that. You should check some unboxing videos just to be sure. I would suggest getting the 290x, it's much faster and paired with that 8 core CPU you will see significant performance increases in games that win run mantle.

Thanks for the quick reply guys :) I was under the impression that using molex addapters was approaching blasphemy - but I'm alot more confident with saving a whole lot of money, not buying an expensive 80+ Gold PSU!