gfx card upgrade advice please

At the moment i have an hd 3850 512mb and amd phenonx4 computer which was bought off the shelf.
As far as i know there is a generic 400w power supply in there as used by fujitsu siemens..
What sort of upgrade can i consider (worthwhile) without having to mess with getting a new power supply?

Advice much appreciated.

Get a HD4770. Google a couple of reviews. You'll see why.

How much are you willing to spend for the card? Without that its hard to say anything beyond the low-end. 400w might be enough for low-to-mid card. 430W was more than enough to run my old 8800GTS640 and it was a powerhog.

ATI just released new high-end DX11 cards. 5850 is the cheapest iirc. Nvidia released just yesterday a new low-end card GT220:
http://www.fudzilla.com/content/view/15698/34/

Thanks for the help, price is not so important…
I just want a noticable difference if possible with a card that will run nicely with the "engine" we have without any issues.

I would say wait a few weeks longer. This new ATI 200$ card is going to push some of the other prices down. A 3850 is not a bad card, there's no need to hurry.

Ok, thanks for the advice, i`ll hang on a few weeks to see if there is a price drop locally for the HD4770.

I'm just going to cut and paste what I recently wrote in another thread.

Right now is not a good time to upgrade imo, especially for graphics cards. Anyone who is looking to upgrade, but doesn't necessarily need to do it immediately, should wait a few more months until nVidia releases their GTX 300 series. Not only will there be more to choose from, but the ensuing price war will no doubt substantially lower the prices of the current lineup.

Good advice there. I`m not in a desperate rush as the card i have is reasonably good for now.
I like to do abit of homework upfront when looking into areas i know nothing much about, you have all helped alot.

Thanks!