Crossfire Radeon HD 6850 or buy a single card?

[pbart]

As my avatar says, I'm an AMD Fanboy. I would prefer to stick to AMD cards; however, I am on a budget, and the most expensive component for me is going to be the video card.

I am currently running one XFX Radeon HD 6850, slightly overclocked.

My question is: Should I buy a second 6850 and Crossfire or, should I opt for a single higher end card that would yield better performance?

Right now I am finding the XFX 6850's for about $120.00, although I could probably get a used one cheaper.

Motherboard compatibility, and PSU are of no concern, I already have the upgrade budgeted in. The motherboard I have planned to buy is: Gigabyte GA-F2A85X-D3H. The power supply budget is flexible, I have a 500w and an 850w PSU available at the moment, but money can be set aside for a new PSU if it's required. This would extend the desired timeline though.

I would like this to become a discussion as this is my first post, and I will try my best to provide any information requested.

 

[pbart]

Thanks for your input. That's a little bit out of my price range though. Even selling the existing 6850 for about $50 I'm still looking to come out of pocket about $100 for the card. Max about $120. Do you have any other suggestions?

Thanks for the input on the single card vs. Crossfire answer, that seems to be the general consensus.