2010 Mac Pro + Yosemite + Radeon 7950

Sorry but that is impossible to see boot screen with PC BIOS on 7950... Unless you are on hackintosh? I have Mac Pro 2008 and recently have flashed my SAPPHIRE HD 7950 OC 3GB GDDR5 950 MHz Edition (using Netkas script) and I do have kernel panics sometimes and can not get on my Del 2414Q 4K monitor work with card using DisplayPort 1.2 (I am trying to get 60Hz), if I set to it the screen just splits screen into 2 parts (and OS X Yosemite 10.10.2 detects like it has 2 monitors attached - strange bug)... Also sometimes my system when gets to login screen freezes for a few secs and than restarts (it could be restarted even up to 4 times) after that it works OK.... So many-many problems with the card driver.... Have done clean installs, reseted SMC and PRAM - nothing helps...

Please belive me i now see boot screen on pc mode (position 2)

P.S. When i switched to 1 position(Mac mod) i sow boot screen is black.

Some AMD version PC cards have dual BIOS and a switch.

Does yours? and are you using legacy mode or UEFI?

Take a look for posts by DPArtor someone with one - like Arsenwho has his working properly now.

Yes i have switcher on my AMD Radeon 7950 Mac Edition

Sapphire have a manual printing error or not current printing about switcher!

http://www.kitguru.net/components/graphic-cards/zardon/sapphire-hd7950-mac-editi on-review/3/

<edit> it took some time after reboot, but the issue persists even with an up to date 10.10.3 install

I tested my 7950 on 10.10.3 and the graphics smoothing at non-native resolutions had improved. However, I still got the 5-10s lockups when trying to load my FB page in Safari. I sold my card to a friend with a 2009 Mac Pro and he reported no issues after he tested it. So there's something about the 2010 Mac Pro and Yosemite that cause this issue IMO. Too bad, because it's a fast card. I'm using a NVIDIA GeForce GTX 680 2048 MB with no issues currently.

Very strange for me. On my Mac Pro 2010 is everything ok with native resolution on led cinema display. I think you have some hardware problem in your display.

What is native resolution your display? Some display have oldest resolutions.

I thought I would never get to say this, but the latest beta version seems to fix it.

No lagging so far, no intermingled keystrokes, seems to work fine as it should have from day zero.

This is the version that has done it. Take note Apple, and, please, next time fix it earlier.

10.10.4 (14E17e)

Nevermind.

Something really improved, but there are still issues. Loading some web pages with plenty of images and JavaScript crap (such as the Spanish newspaper "El Correo") still freezes the system.

I am running latest Yosemite release (10.10.4) and I am still having a weird issue with my Radeon Sapphire 7950 graphics card. After some use, the graphics gets glitchy and slow. I am also unable to efficently run the only two games/simulations I have (X-Plane 10 and Cities Skyline) as the first complains about lack of memory and the second just runs very slow (between 9-12 FPS). These two programs run very smoothly in Mavericks ( I have a separate install in a partition in my HDD). I started looking at some information in Stat Menus and found that the memory in my graphics cards fills very quickly and does not empty after closing open applications. See below example of the Stat Menu panel showing the AMD Radeon HD 7950 running at almost full memory capacity with only Safari running, and low frame rates (13.4). I think Apple has a driver issue with this card under Yosemite

I am running latest Yosemite release (10.10.4) and I am still having a weird issue with my Radeon Sapphire 7950 graphics card. After some use, the graphics gets glitchy and slow. I am also unable to efficently run the only two games/simulations I have (X-Plane 10 and Cities Skyline) as the first complains about lack of memory and the second just runs very slow (between 9-12 FPS). These two programs run very smoothly in Mavericks ( I have a separate install in a partition in my HDD). I started looking at some information in Stat Menus and found that the memory in my graphics cards fills very quickly and does not empty after closing open applications. See below example of the Stat Menu panel showing the AMD Radeon HD 7950 running at almost full memory capacity with only Safari running, and low frame rates (13.4)

I am having the same issues of my Mac Pro(Mid 2010, 10.10.3, Radeon/Sapphire HD 7950 Mac) not booting my monitors using display ports. The Mac Pro will boot a monitor using DVI. The switch is in the Mac position. Any thoughts?

So, I'm considering a sapphire 7950 to go with a duplicate. both will run in a 8 core esrly 2008 mac pro. Anyone have issues with this card on yosemite on this model mac pro? one card will be externally powered.

That should work fine once you work out the power. You will need a new way to get an AC cord inside the Mac for the second power supply. allow me to suggest that the Display card back panel may be the place to make such an incision the size of the AC cord (not the plug-- the plug can be spliced on later).

Compare and contrast to using two 5770, which require only one aux power cable per card.