Two more 260's or 2 5770's

Personally, I'd get a 5870 or 5850 and then crossfire those in a year or two. That's what I'm doing.

I agree with alextheawesome I bought a 5850 with antec 750w PSU so I can crossfire it with a year or two. And really one 5850 is enough for now, buy it and you won't regret it, and in a year or so buy the second one.

And sorry I forgot to answer your question, that's not true, you can have 2,3,4 card on crossfire just like SLI

You're in a tough market segment. In the first months after 5770's came out, the 5770 was dumped in the same class as the 4870 and the 260. Problem was that the 4870 and 260 outperformed the 5770 by about 10 % and the 5770's comeback was that it can do DX11 . Well then Dx11 games came out and it turned out that the 5770 was a bust in th sense that it can't do DX11 either.....well it does support Dx11.... but it can't do 30 fps at 1920 x 1200 when Dx11 is turned on.....and this is in Dirt2 which has only minimal incorporation of DX11 tech.

As a result the GTX 260's price has been driven up by the lack of competition on it's original $155 price category where it's now selling between $200 and $219 ....50% more than it was 45 - 60 days ago. As a result it's tough to recommend one as a single card solution.

As to your "Is DX11 really that much better than DX10" question .... according to the THG review of Dirt2 (see THG home page),the game experience is virtually indistinguishable going from DX9 to DX11. That being said, and with a performance hit THG describes as "colossal", why would you wanna turn DX11 on in that game ? No doubt future DX11 titles will take more advantage of DX11's features but that will mean even heavier loads on the GPU. Unless DX11 has a faster takeup rate than any DX release before it, I don't expect we'll see the "Big Wow" DX11 game which heavily incorporates of Dx11 features and makes us all run out and upgrade until summer of 2011.

So, in short, I think your best bet is a 2nd 260. Yeah, you're gonna get stuck with a price premium at $200 but the alternative is $330 for a pair of 5770's which will be 10% slower than the two 260's. On the other hand, with lots of peeps upgrading to Dx11 cards, there's a decent opportunity in buying used cards. If you are set on being DX11 compatable, I wouldn't invest in anything less than a 5850.

You don't list your resolution or MoBo but keep in mind that with most of the chatter on these boards being 1156 / 1366 based, it can be easy to forget that not all older boards supported SLI or XFire and also that the chipset determined whether it supported SLI or Xfire. You didn't list your MoBo or your resolution which may change how peeps would answer this question.

Need I remind you that Battleforge, and Stalker Pipyat benchmark, both increase performance with DX11. Just because Dirt 2 puts a large hit on performance does not mean that DX11 is not going to work well with other games.

It's like saying PhysX won't work on any modern Nvidia card, because Dark Void drops frames to below 30 fps, even on a 295.

A single 5850 is a better option than two 5770s or two GTS 260s. It will give you an upgrade path to add a second in a year or so when they become cheap.

Thanks for the great info, I have a Gigabyte 1366 EX UD5 mobo with an i7 920. Anyone else have any ideas?

Yes, for a I7 920 build you really should go for a 5850, or even a 5870 instead of a 5770 crossfire, or dual or triple 260

One benefit to a single fast card is it will be cooler than CF or tri-SLI, and quieter. The quiet bard is important to me.

How so, a rowdy crowd is less likely to hear the sonnets.

lol, I can't type  

 

My ignorant advice would be keep with what you have and just spend $180 or so on a GTX 260 OC (Best Buy has them for $181 right now).
I know they say the 5770 is a hell of a beast and the 128-bit interface ....really won't make much of a difference? due to DDR5 and other factors....OK slight me here. I owned a 7600GT which was a very capable card and not just slighted by a 128-bit interface, it kept up with the best of them at the time.
Educate Myself? I'd say that was education to remember, especially with all of the sparring it did in March 2006 on its launch day
Once I threw in an X800XL 6 months later a whole new light emerged.
That bottlenecked 7600GT couldn't churn out enough without even with a good old EIDE HDD with 16mb cache behind it, newest drivers always, generous settings and babied the *** out of it. It could only do so much.
If the Radeon 5770 with its super architecture sending it all down a 128-bit path blows it away compared to a 448 bit path on the GTX 260 then great, but...if I had my choice of a freeway with more lanes open I think I'd ride on that. Fat data flying fast down the 128-bit bottleneck freeway...they are going to be on a streamway frenzy laying out all that new architecture to get the jetpacks rolling. Like a super-overpass with pipelines LOL
Hey, if they can pull it off I'll be on the bandwagon for sure, when prices come down. Believe it when I see it.
.....waiting it out.
Sorry, I'm old n' grumpy and I want my XP back with full support. WAaahh!!