I just bought a XFX Black addition R9 280x from newegg, to put in my 2009 Mac Pro 2.93 8 core. I am waiting for a 8 to 6 pin adapter from
amazon which should come in tomorrow as you can't connect this to work with the stock cables that it comes with in the box.
I am hoping the duel link DVI port works as I want this to connect to my 30 inch apple monitor.
Rob at Barefeats said it worked unflashed for him with the 8 to 6 pin and 6 pins, but I think he was testing it with a 27 apple monitor via mini display port.
I also have a duel link mini display port adapter but when I tried it with my current 5870 the 30 inch display I would get some green dancing pixels on the screen.
Using the duel link DVI connection with the same 5870 works fine.
I will report back on here when I get the adapter cable and see if it works or not and what ports are working.
I would like to flash it down the road but have never done it before so if anyone can point me to a good link on that it would be appreciated.
Does flashing it give you PCIe 2 speeds or just the boot screen? and if so how do you get PCIe 2 speeds.
from barefeats: " The Radeon R9 280X we used was 'un-flashed.' It booted OS X fine but there was no startup screen. Also, when we checked the speed of CPU-to-PCIe-to-CPU communication, it appeared to be running in PCIe 1.0 mode instead of PCIe 2.0. However, unless the GPU intensive app saturates the PCIe 1.0 bandwidth, it will not run any faster in PCIe 2.0 mode."
Rob also said that he only got slightly faster speeds with the card when flashed.
http://www.barefeats.com/tube12.html