Over a YEAR has passed, and we still can't get Apple to add the latest hardware drivers for the newest/latest AMD Graphics Cards (AMD R9 290 series).
We have contacted AMD, and Sapphire, and everyone has pointed their fingers back at Apple, and said that Apple is the only ones that can add the latest graphics drivers to their Apple OS X Operating System.
So the problem lies on Apple, and Apple refuses to update it's operating system to support the newest/latest hardware.
AMD pointed us right back to Apple and said that it's Apple's OS X Operating System, and that it's Apple's job to add and write the newest/latest graphics display drivers to their OS X operating system.
AMD says it's Apple's fault. Sapphire says it's Apple's fault. Apple just refuses to do anything, and ultimately it's Apple's operating system and Apple's closed-ended ecosystem that refuses to allow customers/users to upgrade their Apple Mac Pro computers to the newest/latest hardware.
In the end, I guess the only solution is to abandon Apple Mac Pro products, and just start purchasing "Microsoft Windows PC" computers that we can upgrade and that have PCIe slots that we can just swap out the graphics cards (every year) with the newest/latest graphics card hardware.
Here: http://forums.amd.com/game/messageview.cfm?catid=440&threadid=181379
Here: https://www.sapphireforum.com/showthread.php?33574-2008-2012-Apple-Mac-Pro-with- SAPPHIRE-TRI-X-R9-290-4GB-GDDR5-OC-(UEFI)&p=277467#post277467
Apple seems to be a "dead end" and they don't support their high-end customers and don't seem to support Apple Mac Pro (high-end) users. Apple only seems to be concerned about selling iPods and iPads and iPhones, and they've abandoned their HIGH-END Apple Mac Pro users that want HIGH-END workstations for professional use.
I guess if you want a high-end workstation, you have to go back to buying a Microsoft Windows PC, and start going back to using the Adobe suite, and just completely abandon Apple and Apple products all together. (Apple is not in the business of designing or selling "high-end" products anymore). Apple just designs low-end "overpriced" hardware, that you can't upgrade, and must toss in the garbage every other year, because you can't upgrade it.
Apple has been heading this way for years, and the newest/latest "Black Shiny Trash Can" (that is NOT upgradeable and has no upgradeable PCIe slots and no way to even upgrade the video cards) and Apple has turned into a "disposable" computer company/business that just builds "All-In-One" garbage computers (that become extremely outdated and must be thrown away every other year, because they are not upgradeable) and you can't swap out video cards using standard COTS (Commercial Off The Shelf) latest Graphics Card adapters, and we can't even get the latest Mac OS X operating system to support the newest/latest graphics display hardware, it seems like our only choice (as others have stated before) is to abandon Apple products and begin moving/migrating back to Microsoft Windows 8.1 Pro machines.
We can't get Apple to support their customers or update their operating system or support the newest/latest hardware in their operating system, so it seems to be a "dead end" ecosystem, and Windows 8.1 Pro and using standard PC hardware is probably a much cheaper/affordable route and it's a long-term solution, because Apple seems to come out with one nice product (every ten years) and then they don't support the product or it's users, or don't follow-up with Apple OS X operating system upgrades, and then you are stuck with very old outdated hardware because you can't even get the newest/latest drivers for the latest graphics cards/hardware.
The only solution is to boot directly into Windows 8.1 Pro, and use Windows drivers, but then why even own a Apple Mac Pro if we can't use Apple OS X and can't even use our OS X software, and the only solution is to use our Apple Mac Pro as a Windows PC?
We're really disappointed in Apple and how Apple fails to update Apple OS X and fails to support the latest graphics cards (such as the AMD R9 290 graphics card).
I think 2014 is the last year that we are going to deal with Apple. Starting in 2015, as part of our 2015 New Year's Resolution, I guess we'll start e-baying our Apple Mac Pro equipment, or selling it (as salvage) and begin purchasing standard Microsoft Windows 8.1 Pro high-end workstations, and get away from the old legacy dead-end Apple garbage hardware and dead-end Apple OS X operating system.
It shouldn't be this hard, just to get some graphics drivers released to support the latest graphics card (which has been out for over a year now). The Radeon R9 290 graphics cards were out in mid 2013 (for over a year and a half, almost 2 years now...) and we are already coming up on 2015, and Apple still hasn't added drivers support for the R9 290 series graphics cards to it's latest Apple OS X 10.10.1 Yosemite.
It's a shame, but Apple has really gone downhill over the past few years. Nothing but really old and outdated hardware, and even their "latest" Apple Mac Pro is 2-3 year old hardware (that Apple is marketing as "new") and it's non-upgradeable, and you can't even run/install the latest graphics cards into it.
Apple is dead-end and it's not a place for "high-end" users anymore. I guess Apple doesn't care about it's "high-end" user market anymore, and is just interested in designing silly iPhones and iPods/iPads.
