I'm thinking of replacing my X1900 XT with the 8800 GT in My original 2.66 GHz Mac Pro. If anyone has an 8800, I'd appreciate hearing how Civ IV is running for them.

Only vanilla Civ4 here, but it seems to run great.

That said, I haven't played a lot of Civ4 with it yet. So its possible there are glitches I didn't encounter.

I have a first generation iMac with a 256 MB 7600GT card. When I got tired of rebooting to play BTS and I wanted something to run Bioshock well, I built a PC with a 8800 GT card. The difference in running BTS between the two machines is more due to the PC just being faster, I don't think the graphics card is a big factor. When playing Bioshock though the graphics card makes a huge difference.

So I wouldn't buy the card hoping to see a big difference in Civ. But if you had another excuse I would. I do think the nVidia drivers are better on the Mac side, so I think that it will do better in Civ because of that.

I should be getting a GF8800 upgrade card for my 1st generation MacPro next week. I'm getting it as I bought the GF7300GT originally, expecting to be able to get a better card later, and not wanting to pay significantly more (and wait longer) for the X1900. So I will be able to give you some info, but I will not be able to give you a direct comparison against the X1900.

From the reviews I've read, I believe the GF8800 is not a significant improvement on the X1900 for normal Pro applications, but that it should be better for games.

Thanks for the info, guys. Actually, I don't expect a great difference, but I'm on my second X1900 XT since Apple replaced the first under warranty. I want a card I can trust for the long haul since warranties don't last forever and eventually the newest cards won't be compatible. Besides, this way I'll have a spare.