+1 here (actually it's branded R9/280X, but since the EFI part comes from a 7950 it's identified as such)
Just because I've done so much friggin' research and learned so much:
The EFI that is available from Netkas' site (
http://forum.netkas.org/index.php/topic,5619.0.html) and others will work with almost any "Tahiti" chipset AMD card. Tahiti = HD 79xx, and R9 2xx(X).
(Disclaimer) That's not an absolute guarantee as there are probably ~100 variations on the reference design, but all reports on dozens of cards say it works. Follow the instructions carefully using the rom from
your exact card and you'll be fine. The BIOS switch on most variations of the card make it all but fool-proof. I was nervous about doing it, but it was far easier than many other things I've done with "Kate" (My cMP1,1). Again, I thank MacVidCards.
Here are some fine points that will probably not have any impact in real-world use. They are somewhat relevant if you're shopping for used cards on eBay. For example, an R9 280X is theoretically worth a bit more than an R9 280 and the R9 2xx cards are probably newer that any HD 79xx cards:
- R9 280 (no X) is a re-branded HD 7950 with a few very minor tweaks, as reported HERE
- Similarly, the R9 280X is a re-branded HD 7970
- The general consensus is that there is so little difference between 7950 and 7970 that it's not worth paying the premium for the 7970.*
- Certain versions of the 7950 can match and even outperform certain versions of the 7970 when they're overclocked. (I can't find that reference in the hundreds of pages in my history, you can google it yourself or take my word for it)
*I bought both the 7950 and a 7970GHz edition Gigabyte branded cards. I like the 3 fan Windforce design and Gigabyte has the exact BIOS for every card they make on their site. I'll spare you the specs of the two cards and say that the 7950 is slightly overclocked vs. a reference 7950 and the GHz edition 7970 is the absolute high-end in terms of factory overclocked 7970's. Benchmarks aside, I can
barely tell the difference. The 7970 cost me $50 more than the 7950. Is it better? Sure. Is it $50 better? Probably not.
Because I'm strange and like to research and experiment, I flashed the R9 280X bios onto my HD 7970 GHz editions. The clock speeds lowered to those on the Gigabyte website and the card performed flawlessly on both El Capitan and Windows 8.1. When I tried the same bios on the 7950, I got a BSOD on the Windows side. That was enough experimentation and I restored everything to factory settings.
One last note for Wojtek - If you care what Apple System Profiler says you can use Hexfiend (free) to change the string so that it reads R9 280, just open a copy (always be safe), search for HD 7950 (there are 2 instances) and replace it with R9 280X or anything you want, it's just a string that is passed.
-iMattux - Doing the research so you don't have to since 2001 (R)
