Upgrade recommendations for a 1,1 MP w/ a 4870?

[SwingCat]

Is anyone aware of a video card that would be a worthwhile upgrade for a 1,1 mac pro that has a flashed 4870 and is running Lion? I'm looking for one more upgrade to tide me over until I can afford another mac pro. I was thinking about the 6870 but I've heard it's not much of an upgrade. Anyone know of a a card that works w/ Lion that's worth it?

 

[drbrog]

I think I've seen the 5770 used successfully. I have a 4870 so I can't say for sure. Maybe do a search to see if I'm correct.

 

[Etherz10]

5770 works flawlessly with 1,1 - apple version obvs