Will the R9 290 be good for my build?

Okay, so i'm thinking about getting an R9 290 for my build the problem is i think there might be some incompatibility issues that may occur so i would like to verify if any of this would happen.

Current Build:

AMD FX 6300

Asus M5A97 LE R2.0

Radeon HD 6640

Corsair CX 500w

Proposed Graphics Update:

XFX R9 290 dd 

or

Sapphire R9 290 Tri-x

I can see where the possible problems can be as my power supply is only 500 watt but when i ran a stress test my computer was only pulling 149 watts out of the wall. The max tdp of the R9 290 is 275 watts so would there still be problem here? as the watts would be under the 500 watt power supply threshold.

You will be fine with your power supply

my 780 has a tdp of 250 and I'm running a 450 watt PSU

TDP does not equal how much juice gets pulled from the wall.

The 290 will be completely compatible with your system and should give your system a good performance boost.

I'd go Sapphire. They make only AMD GPUs and they are pretty much the best on the market.

I was taking that into consideration but xfx offer lifetime warranties plus their amd only too.

Sapphire TriX cards are better in every way.

I second that R9-290 Tri-X. i own one OC'ed to 1070mhz (i got owned by the silicon lottery =[ ) and i've never seen it go above 80C. 

If you go with the tri-X OC, like i did, if it does not have a vbios of 0.45xxxxxx then you will be having errors because of the new amd driver. if you dont get an oc version then you will be fine. just thought you should know. but all i had to do was flash a new bios and it works perfectly.

As far as cooling goes, Tri-X > DD

 

That said, in a few months, the 300 series should hit the market. You could wait until then, but I really hate waiting for "the next big thing" like that. Up to you though, just thought I would let you know that it is an option.

Just want an improved performance now tbh i know that the 300 series may be better than offerings from nvidia in the coming months which would be cool thing to see happen but im fine with the 200 series plus the R9 290 is dirt cheap right now.

Just looked and i have indeed ordered the OC version so i will be doing that is there a guide for this on sapphire's site or AMDs? 

 

Radeon R9-290   - 31A and a 550W psu minimum

This was taken from http://forum-en.msi.com/faq/article/power-requirements-for-graphics-cards

I like to have at least 100watts above from the bare minimum GPU requirements.

31A is a number to take note of

550w psu is not.

Looked at the pci power its able to handle 31A

http://www.tomshardware.com/reviews/power-supply-review-80-plus-bronze,3587-4.html

I think its on the +12 v rail 1 it can handle up to 38a