"Had same problem. (2008 Mac Pro/10.5.6 - no ATI 4870 drivers.) Go to: http://www.sendspace.com/file/gvsi12 and install these drivers until 10.5.7 arrives. They work here with MacPro early 08 dual quad, 4870 and 24" LED Cinema Display.
-Jack"

(Earlier post follows)
And here's a follow-up mail from one of the readers that installed a 4870 card in his 2008 Mac Pro on a call from Apple support Thursday night regarding drivers:

"Mike, Actually, "Paul" from Apple just called me unsolicited (I never called or emailed support) and left a voicemail. He said that the card was shipped prematurely, that the software is not ready yet and that the card will likely not function correctly. He said that it would be available as a download via Software Update as soon as it was ready. He also said that they would call again to let me know when it was available. I'm guessing that this would be the 10.5.7 update? Or perhaps an ATI specific update? (I suspect 10.5.7 w/driver update) I would never expect to get such a proactive support call, even from Apple... impressive. (I was surprised at calls vs emails - but over the next 24hrs several other readers said they also got a call.-Mike)

As for your other questions, Apple System Profiler's Graphics/Displays shows that Quartz Extreme is Not Supported and Core Image is Software. The ROM version is listed as 113-B7710F-176. (Emphasis mine - a 4870 card shipped in a 2009 Mac Pro last month had rom 113-B7710C-176, although same EFI driver version as below.-Mike) Here's the ASP info (2008 Mac Pro):

Chipset Model: ATI Radeon HD 4870
Type: Display
Bus: PCIe
Slot: Slot-1
PCIe Lane Width: x16
VRAM (Total): 512 MB
Vendor: ATI (0x1002)
Device ID: 0x9440
Revision ID: 0x0000
ROM Revision: 113-B7710F-176
EFI Driver Version: 01.00.318
Displays:
Display:
Resolution: 1920 x 1200
Depth: 32-bit Color
Core Image: Software
Quartz Extreme: Not Supported

Thanks, Andy"

With the later 10.5.6 build/drivers included w/2009 Mac Pros there's also "Rotation" support listed (as well as "Hardware Accelerated" Core Image and Quartz Extreme support of course).

"I received my iMac 24"/2.93GHz/ATI 4850/1TB HD six days ago. The first two days I was freeze free with both Airport and Bluetooth running. I was feeling like I was one of the lucky ones, then on day three the freezes started. They were quite random.
It would freeze while only using Firefox and not while playing Halo with max settings. The freezes became more frequent so I broke down and called Apple. After telling them what was going on I was bumped up to a level 2 tech. He sent me an Apple Data Capture program that saved a file I emailed back to him that obviously recorded my Console log files. He was going to send it off to engineering and would call me back within a week. They offered to send me a replacement but from what I have read those that received replacements have the same freeze issues.
After reading a couple of posts on Apple's discussion board regarding no freezes after turning off Airport and connecting via ethernet, I gave it a try. I haven't had a freeze since and it's been four days.
I have had my bluetooth Mighty Mouse stop working on two occasions. I used a wired mouse to toggle bluetooth to off/on and it would start working again. (he's not alone in BT/mouse problems as reported earlier (from new mac pro owners also))
It may be related to the 4850 or it may have something to do with the bluetooth update that is suppose to be included in 10.5.7. When it's not freezing this is an amazing machine. I do a fair amount of photo editing and am not bothered by the glossy screen. The screen however was way too bright and couldn't be turned down enough from the keyboard to properly calibrate it. (A custom colorsync profile with adjusted gamma didn't help?-Mike) A freeware prefpane called Shades took care of that.
- Rich"

Earlier replies follow.

"My new iMac froze solid (requiring a hard shut down) twice in its first two days. On the third day it froze four times within an hour. The freezes were all during graphically intense use; WoW at max settings. I use wired Ethernet but also have WiFi, Airport, running to connect to an Airport Express which links iPhone to the stereo in the living room. No music was being served through WiFi at the time of the freezes. Bluetooth is on and connects to a Mighty Mouse which is usually idle because I have a wired trackball.

After turning Airport off, the machine has run beautifully ( what a beautiful computer!). I have played WoW at least 15 hours without problems. I have not had the guts to turn Airport back on and see if the freezes return. Yesterday, I talked to an Apple Tier Two tech wishing to establish a case number and history. He sent and had me run some sort of log file; ACCD. This file in turn was passed on to Apple Engineering. Interestingly, this little program was run without Airport on. No need, I was told.

The Apple tech says there is a interaction conflict between Airport and ATI 4850. They hope to have a software solution soon. It may come with OSX 10.5.7 which is soon to be released (he didn't know the date). He volunteered to call me back after hearing from Apple Engineering and also gave me his phone and extension number. He did say that Apple asks you not to return the computer at this time.
-Jim"

And a reply this morning from Ken who had noted last Friday he had turned Airport on - so far he says still no freezes:

" Yup, for the most part all has been crash-free. I use the new iMac for 8-12 hours every day for work and personal use, including web design, Photoshop, word processing, massive web trolling, video via web and dvd, etc. Airport is on all the time, and is used to stream audio throughout my home for 8 hrs + every day. My main network connection is cat6 gigabit ethernet within my home, out through a cable modem to get to the internets.

There have been a few weird incidents, though. This morning, for example, my second monitor, attached via DVI, went MIA until a reboot. Then, my USB Plantronics headset and separate USB iMic external stereo also stopped working (I have a USB hub, but neither of those audio devices are on the hub; they are plugged directly into the iMac). The system saw them, but there was no audio input or output. Another reboot solved that, and all has been fine in the three hours since. These incidents were the first of their kind, but are symptomatic of other small bouts of weirdness that pop up every second or third day. Hard to know the cause, and given the vast variety of software and hardware I have plugged into a brand new machine, it is amazing more issues haven't popped up yet (remember, this is a Migration Assistant system, with very few pieces of software having been installed 'naturally').
(I asked next time he had a quirk like that to check the console app messages to see if there were any related entries (they're timestamped)-Mike)

I am very pleased with the machine thus far. The speed of everything is my favorite part...
My least favorite part is the glossy screen. This is my first glossy monitor, and while images certainly pop, the glare is not worth the trade off. I guess that ship has sailed, however.
-Ken"

"Mike, At this time we have made no official announcements reguarding mac products. I would not have any info available unfortunately.
Regards,
Daniel B.
EVGA"

I guess it's just not filtered down to general sales staff at EVGA yet, as here's a later reply from Nvidia (they later sent me a better contact at EVGA who's aware of the product - but he replied he could not comment -yet- on the product, but would once it was official):

" Hey Mike. Yes its true. Sorry we should've got this to you yesterday to post.
-Derek
(Nvidia)"

Derek had hinted at more (consumer) models being available in the future when I asked him back on the 20th after the PR on a Mac Quadro FX 4800 being sold by several partners (PNY, Elsa, etc.).
IMHO it makes more sense for Nvidia partners to sell (consumer) cards like this for the Mac, rather than (only) the very expensive ($1700+) Quadro FX, which I suspect Apple will get the lion's share of Quadro card sales. (Leaving the other companies mentioned in Nvidia's PR on the Mac Pro Quadro seeing low sale volumes, which I fear would have them reluctant to offer other Mac models in the future. Granted profit margins for the Quadro are much higher than GTX series.)

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