Is it worth going for a Radeon 7790 at this point (for £85)?

[Pemalite]

Anandtech's Bench is better to compare cards.
http://www.anandtech.com/bench/GPU13/583

I agree with Vashyo, grab a Radeon 7870, it's got great price/performance.

Or, wait for Volcanic Islands to launch, majority of that line-up should be re-branded cards, even still it should bring with it some price drops on the 7000 series.

Also, Isn't that Athlon 2 x4 getting a little long in the teeth? Thought about picking up a Phenom 2 x4 dirt cheap off ebay or something for that extra boost? Or even a Phenom 2 x6. :)
Then sell your Athlon 2 x4 CPU which could go towards paying for the Phenom!