MP 1,1-5,1 Sapphire HD 7950 Mac edition problem

[ferranrobuste]

Hello,
I have a mac pro 5.1 from 2010 (2x2.40, 64 gb ram, Mojave in a ssd), with a Sapphire HD 7950 3 gb mac edition graphics card. Until now I had it connected to a 27-inch, 2K AOC monitor, and everything works perfect at 2560x1440 60Hz.
I have bought a new LG 27UL650 4K monitor. When I connect it with the Mini displayport to displayport cable, the screen goes black and the mac does not start.
On the monitor, I can change the version of the displayport connector 1.1, 1.2 or 1.4. If I select 1.2 or 1.4 the mac does not boot, I have read that the HD 7950 card does not support versions higher than DP1.1.
The problem is that if I select the DP1.1 version on the monitor, the mac boots, but I can only select these screen resolutions:
3840x2160 (low resolution) at 30Hz
1920x1080 at 30Hz
1280x720
1080p
I can't select for example 2560x1440 at 60hz, just these 4 resolutions at 30hz ...

Besides, if I click "alt" + select "scaled", I see other resolutions, but it always says "(low resolution)". If I choose 2560x1440 (low resolution), it seems to lose definition.
Once the mac is started, if I change the monitor to the DP1.2 version, all the resolutions appear without the "low resolution", and if I select 2560x1440 it looks much better than with the DP1.1 version, 2560x1440 low resolution.

What can I do to be able to select other resolutions, such as 2k at 60 hz, without "low resolution"?
Thank you very much for the help!

 

[zedex]

Ahhhh - the great white whale.. Sapphire HD 7950 Mac Edition
I've owned three of them and they're a great disappointment.. (but I was NOT going back to 2K@60Hz max resolution)

Here are the THREE issues you will be [eventually] dealing with (including the first one described above)..

(1) You will first wonder about monitor settings....... which version of DP will depend on which OS you are using - anything after 10.9 should be ok with 1.2 or above (but all of that is beside the point - set your monitor to auto select DP generation OR select 1.2)

(2) The next issue is the DUAL-BIOS switch on the GPU itself. Look closely - took me weeks to realise it existed..
Dip-switch position 1: the "native mac boot screens" ROM. The white HD7950 can only do 4k@30hz if you want to see a boot screen.
Dip-switch position 2: the Windows/PC stock standard ROM. The white HD7950 can now do 4k@60hz BUT no boot screen.

(3) Even when I cracked the 4K@60Hz code, I was irritated by a constant screen-flicker that a member of this forum [ the GPU guru @h9826790 ] helpfully pointed out, was a "known issue" with this GPU.

So.. how to get where you're going..?

The ONLY solution to solve everything (4K@60Hz AND boot screen access):

STEP 1: Connect a second basic monitor to the GPU (mine is a beautiful Dell P1913S with DP*, DVI-DL and VGA).
STEP 2: Use Dip-switch position 1 (for "native mac boot screens").
STEP 3: When you power on your Mac Pro - the boot screen will be available/visible on the 'el cheapo' monitor.
STEP 4: Your desktop will appear on the 4K display after the boot process finishes
USING SYSTEM PREFERENCES
- you can now set the 'Desktop 2' display to run 4K@60Hz
- then you can make the 4K primary (dragging header from small monitor to large monitor)

Regarding the third issue - as long as you have 2 or more displays running from this card, it forces the clock speed to run higher and this eliminates the screen flicker.

* You can see at this point that a lot can go wrong with permutations and combinatorics - so for the sake of accuracy you need to know that both monitors (4K and 1280x1024 P1913S) are connected to HD 7950 via mDP 1 and mDP 2. This is my known good config.

And don't forget about compliant cables (DP1.2+). Good luck and AMEN!

 

[ferranrobuste]

sorry, duplicate post

 

[ferranrobuste]

Ahhhh - the great white whale.. Sapphire HD 7950 Mac Edition
I've owned three of them and they're a great disappointment.. (but I was NOT going back to 2K@60Hz max resolution)

Here are the THREE issues you will be [eventually] dealing with (including the first one described above)..

(1) You will first wonder about monitor settings....... which version of DP will depend on which OS you are using - anything after 10.9 should be ok with 1.2 or above (but all of that is beside the point - set your monitor to auto select DP generation OR select 1.2)

(2) The next issue is the DUAL-BIOS switch on the GPU itself. Look closely - took me weeks to realise it existed..
Dip-switch position 1: the "native mac boot screens" ROM. The white HD7950 can only do 4k@30hz if you want to see a boot screen.
Dip-switch position 2: the Windows/PC stock standard ROM. The white HD7950 can now do 4k@60hz BUT no boot screen.

(3) Even when I cracked the 4K@60Hz code, I was irritated by a constant screen-flicker that a member of this forum [ the GPU guru @h9826790 ] helpfully pointed out, was a "known issue" with this GPU.

So.. how to get where you're going..?

The ONLY solution to solve everything (4K@60Hz AND boot screen access):

STEP 1: Connect a second basic monitor to the GPU (mine is a beautiful Dell P1913S with DP*, DVI-DL and VGA).
STEP 2: Use Dip-switch position 1 (for "native mac boot screens").
STEP 3: When you power on your Mac Pro - the boot screen will be available/visible on the 'el cheapo' monitor.
STEP 4: Your desktop will appear on the 4K display after the boot process finishes
USING SYSTEM PREFERENCES
- you can now set the 'Desktop 2' display to run 4K@60Hz
- then you can make the 4K primary (dragging header from small monitor to large monitor)

Regarding the third issue - as long as you have 2 or more displays running from this card, it forces the clock speed to run higher and this eliminates the screen flicker.

* You can see at this point that a lot can go wrong with permutations and combinatorics - so for the sake of accuracy you need to know that both monitors (4K and 1280x1024 P1913S) are connected to HD 7950 via mDP 1 and mDP 2. This is my known good config.

And don't forget about compliant cables (DP1.2+). Good luck and AMEN!

Thank you very much for the explanations...
I had not planned to connect 2 monitors permanently ... only with the 27-inch I have enough ... Is there any way to have 4K with the Sapphire HD 7950 Mac Edition and an HDMI cable?
I've tried two different HDMI cables, and there is no resolution to choose from in the "scaled" box, the box is blank, and I can't select anything ...

 

[panjandrum]

You might simply consider dropping in a Radeon 560 (about the same GPU power as your 7950 I think), or a 580 (about 2x the power, a pretty substantial upgrade but also quite a bit more $). You'll have a modern card that supports modern resolutions without any issues. Keep the 7950 Mac Edition around in case you ever need a boot screen.

Will probably save you so much headache and work that it will be worth the $. Note that if you use anything that uses the GPU hard you'll be far better off with the 580 than the 560. If not, then the 560 will suit you just fine.

 

[ferranrobuste]

Well, in fact I understand that the screen is already working at 4K (but at 30 Hz), and with the user interface scaling to 1920x1080 (this is how it appears in the system report - graphics / displays).
The only thing I would like to achieve is 4k at 60hz, and scaling to 2560x1440, so that everything looks a little smaller, but not as much as 4k. Is this possible without needing a second monitor?
Thanks!!

 

[ferranrobuste]

You might simply consider dropping in a Radeon 560 (about the same GPU power as your 7950 I think), or a 580 (about 2x the power, a pretty substantial upgrade but also quite a bit more $). You'll have a modern card that supports modern resolutions without any issues. Keep the 7950 Mac Edition around in case you ever need a boot screen.

Will probably save you so much headache and work that it will be worth the $. Note that if you use anything that uses the GPU hard you'll be far better off with the 580 than the 560. If not, then the 560 will suit you just fine.

Thank you! Yes, I had already thought about upgrading to a 580 ... the problem is that right now the RX580 are not available in most stores, or are sold for more than double their usual price ... so I will have to wait a little...

 

[panjandrum]

Well, in fact I understand that the screen is already working at 4K (but at 30 Hz), and with the user interface scaling to 1920x1080 (this is how it appears in the system report - graphics / displays).
The only thing I would like to achieve is 4k at 60hz, and scaling to 2560x1440, so that everything looks a little smaller, but not as much as 4k. Is this possible without needing a second monitor?
Thanks!!

Fundamentally that's a relatively 'old' video card that you've got, and while the PC version would probably work just fine doing what you want to do in a PC running Windows, Apple-specific video cards almost always had some weird limitations. Your system will support an array of modern AMD video-cards for PCs right out of the box, no need to flash the rom or do any tinkering. Only downside is you won't get a boot screen. Now that can be a BIG downside under the right circumstances, which is why you want to keep your old card around. But if you upgrade your vid card you should be all set for what you want to do. It will almost certainly be worth spending the $ rather than having the headache of trying to get things working with that old card you currently have. No second monitor necessary.

EDIT: Ah, I see you've already considered that but that the 580 is sold out. Bummer. Try lesser-known vendors, maybe Micro Center will have one, for example.

 

[zedex]

Is there any way to have 4K with the Sapphire HD 7950 Mac Edition and an HDMI cable?

NONE. I wanted an Apple-certified (blessed) GPU to run my new 4K display back in 2016. It took a lot of research, testing and money to get the complete picture.

No 'blessed' card gives you a 4K boot screen.
The two shipped options absolutely do not (GT120 and 5770/5870).
The 2 "aftermarkets" (there are only 3) that bump up against the possibility of 4K are NVIDIA Quadro K5000 and Sapphire AMD Radeon HD 7950.
These will run 4K@60Hz through Displayport ONLY. Apple GVA Frameworks/ GPU Kexts were never designed for 4K@60Hz display output.

Remember, GPU has to be capable AND OSX (system) drivers have to be present. The HD7950 and K5000 were released and fully supported for the display resolution options embedded in OS X 10.8 and 10.9 - because both certified GPUs are in fact VERY old.

Then a whole lot of other stuff comes after which is difficult to abridge into one paragraph. Suffice to say.. somewhere between 10.10 and 10.12 almost ALL native 4K support issues were resolved from DP1.2 compliance to HDMI 2.0 adoption.

Polaris GPU generation (RX480/580 etc) is the minimum threshold for using an HDMI connector. Otherwise you are simply not getting 4K@60Hz without a DP connector OR a DP to HDMI 2.0 4K@60Hz ACTIVE adapter.

 

[ferranrobuste]

NONE. I wanted an Apple-certified (blessed) GPU to run my new 4K display back in 2016. It took a lot of research, testing and money to get the complete picture.

No 'blessed' card gives you a 4K boot screen.
The two shipped options absolutely do not (GT120 and 5770/5870).
The 2 "aftermarkets" (there are only 3) that bump up against the possibility of 4K are NVIDIA Quadro K5000 and Sapphire AMD Radeon HD 7950.
These will run 4K@60Hz through Displayport ONLY. Apple GVA Frameworks/ GPU Kexts were never designed for 4K@60Hz display output.

Remember, GPU has to be capable AND OSX (system) drivers have to be present. The HD7950 and K5000 were released and fully supported for the display resolution options embedded in OS X 10.8 and 10.9 - because both certified GPUs are in fact VERY old.

Then a whole lot of other stuff comes after which is difficult to abridge into one paragraph. Suffice to say.. somewhere between 10.10 and 10.12 almost ALL native 4K support issues were resolved from DP1.2 compliance to HDMI 2.0 adoption.

Polaris GPU generation (RX480/580 etc) is the minimum threshold for using an HDMI connector. Otherwise you are simply not getting 4K@60Hz without a DP connector OR a DP to HDMI 2.0 4K@60Hz ACTIVE adapter.

Ok, I get it...

So, I could get 4K at 60hz by selecting the DP1.2 version on the monitor, but then I would need another monitor, as you have explained to me, since otherwise the mac does not start with the DP1.2 version and at 4K.

Perhaps the best option will be to upgrade to a RX580, when the price returns to "normal" ...

In fact, the Mac 5.1 belonged to a friend, he no longer used it and he gave it to me (but he kept an RX580 that he had installed to put it on another pc, and he gave me the previous HD 7950), I have a mac mini and I wanted to test the Mac pro 5.1 for a while to see if everything works fine before updating it... so for now maybe I can use it at 4k 30hz (scaled to 1920x1080), and if everything else works fine I can upgrade the graphics card...

Basically I will use it for photo editing with Capture One and some video editing...
Thank you very much for the help!

 

[ferranrobuste]

Your system will support an array of modern AMD video-cards for PCs right out of the box, no need to flash the rom or do any tinkering. Only downside is you won't get a boot screen.

I guess with a RX580 I could have a boot screen if I install Opencore? I've tested it by installing it on a usb stick, following a tutorial on this forum, and it seems to work fine with Mojave...

 

[zedex]

I've got the RX580 - it's really good enough by most measures. Best thing is that you can slip it in to SLOT 4 cleanly..

check this out AMAZING NEWS - 2.5 Width GPUs will never again interfere with SLOT 2

 

[zedex]

PS - you should be able to use 4K@30Hz without issue on your HD7950

 

[ferranrobuste]

I've got the RX580 - it's really good enough by most measures. Best thing is that you can slip it in to SLOT 4 cleanly..

check this out AMAZING NEWS - 2.5 Width GPUs will never again interfere with SLOT 2

Wow!! Very interesting!

 

[zedex]

Don't forget to locate your DUAL-BIOS dipswitch and play around with that!!