MP 1,1-5,1 MAC PRO 5,1 Tower run 2 different GPUs together

[FlyingFortress]

Making a long story short, I have ordered a Radeon Sapphire 580rx to replace my unflashed (not Metal) Nvidia GTX 980ti (which hates my newest HS ugrade build, long story).

My question here which I have seen touched on but not SPECIFICALLY covered is can I run both a 5770 AND THE 580rx together for my 3-monitor set up? The 580 is the retail unflashed model. I have an external 500w power unit that I needed for the Nvidia card but the 580 apparently only needs the 2, 6-pin outputs into an 8-pin splitter. The 580 is said to need no external power. If I run the old 5770 in the second 16x PCIE slot I can power it from the external unit via a 6-pin which is all it needed when it was powered from the logic board.

My intention is to run 2 of the wide aspect HP monitors off of the 8gb 580 while running the third in the monitor array off of the 1gb 5770.

I am aware that there may be boot screen issues (never got one running my GTX 980ti) but I’m concerned about what I‘ve seen here about Macs not liking running 2 cards with 2 different sets of specs and drivers mountEd on the same logic board.

Back in 2013 this Mac of course ran 2 5770s out of the box. Years later when I installed one 980ti along with one 5770, I got black screens all the way around. So of course I ran the 980 by itself. I mostly run Adobe Suite for work but X-Plane 11 for fun and that’s what needs the high frame rate.

I have just upgraded to HS from S and I’ll stay there for a while. I have a 12 core 306 dual processors. I’m selling the 6gb 980 on Craigslist.

Any input from you that you think might be relevant would be much appreciated.

 

[tsialex]

Works with High Sierra, don't work with Mojave at all. High Sierra RX 580 drivers are not optimal while Mojave drivers are excellent. You can run 3 displays without problem with a RX 580, no need to use the HD 5770 at all.

Mojave only works with supported GPUs and HD 5770 is not supported anymore.

 

[StuAff]

As @tsialex said, no need for the 5770 if you want to run multiple displays. All the ports on the RX580 will work without a problem. The 5770 will work in Mojave, my GT120 did- but only as a basic display adaptor, no acceleration so very, very slow indeed. Only worth it to get a boot screen when you need one. The Mojave installer, however, will check that all installed GPUs are supported and will not allow installation if the 5770's in.

 

[FlyingFortress]

Works with High Sierra, don't work with Mojave at all. High Sierra RX 580 drivers are not optimal while Mojave drivers are excellent. You can run 3 displays without problem with a RX 580, no need to use the HD 5770 at all.

Mojave only works with supported GPUs and HD 5770 is not supported anymore.

Thanks so much, tsailex AND StuAff. Again I have no plan to upgrade to Mojave so the restrictions there on the 5770 will not apply to me for the foreseeable future. I’m thinking that I will only want to share the 580 across the 2 monitors that I’ll be running X-Plane on and I’ll dedicate the 5770 to the third screen in my array to use as my boot or “native” Mac screen. It will not be a “game” screen, just one that sees and can use what the 5770 still has to offer. I can assign the 2 “580 screens“ to retain my best FPS for this sim. The 8gb 580 Should run those screens which plenty of headroom to spare. Of course this assumes that I can run both cards TOGETHER and that their individual performance won’t suffer.

I’m thinking that it’s going to come down to trial and error when my parts come in. I will certainly share my results in HS here. I was amazed by the amount of posts here about video cards and legacy Mac Pros 5,1 and under. I’m just tying to do no harm during this trial and error.

 

[tsialex]

Thanks so much, tsailex AND StuAff. Again I have no plan to upgrade to Mojave so the restrictions there on the 5770 will not apply to me for the foreseeable future. I’m thinking that I will only want to share the 580 across the 2 monitors that I’ll be running X-Plane on and I’ll dedicate the 5770 to the third screen in my array to use as my boot or “native” Mac screen. It will not be a “game” screen, just one that sees and can use what the 5770 still has to offer. I can assign the 2 “580 screens“ to retain my best FPS for this sim. The 8gb 580 Should run those screens which plenty of headroom to spare. Of course this assumes that I can run both cards TOGETHER and that their individual performance won’t suffer.

I’m thinking that it’s going to come down to trial and error when my parts come in. I will certainly share my results in HS here. I was amazed by the amount of posts here about video cards and legacy Mac Pros 5,1 and under. I’m just tying to do no harm during this trial and error.

While you can use both cards with 10.13.6, you won't have any speed gains doing so and you will have problems using dissimilar dual GPUs, usually weird KPs or artefacts.

If you are doing it for the sake of pre-boot configuration support, learn to use OpenCore and enable OpenCore BootPicker with your RX 580.
[automerge]1592150221[/automerge]
Btw, High Sierra support ends the day Apple releases 10.16, around September. Apple only support the current macOS release (will be 10.16 then) and the two previous (will be 10.15 and 10.14 then).

Doing all this trial and error for a macOS release that is obsolete in less than three months don't make much sense.

 

[MIKX]

FlyingFortress

The Sapphire Dual-X HD 7070 3 gb can be EFI flashed ( I have one - flashed ) and will run Mojave with EFI pre-bootscreens. It also has the DUAL BIOS switch = very handy !

If you buy one I have the flashed EFI ROM if you need it.
Not as fast as an RX 580 8gb but still very respectable.

As you already have an HD 5770 flashing a Sapphire Dual-X HD 7970 would be pretty easy.

 

[FlyingFortress]

While you can use both cards with 10.13.6, you won't have any speed gains doing so and you will have problems using dissimilar dual GPUs, usually weird KPs or artefacts.

If you are doing it for the sake of pre-boot configuration support, learn to use OpenCore and enable OpenCore BootPicker with your RX 580.
[automerge]1592150221[/automerge]
Btw, High Sierra support ends the day Apple releases 10.16, around September. Apple only support the current macOS release (will be 10.16 then) and the two previous (will be 10.15 and 10.14 then).

Doing all this trial and error for a macOS release that is obsolete in less than three months don't make much sense.

Here’s the latest. I installed the RX 580 last night in my 2012 Mac Pro, by itself, without the second card (5770). Everything was fast and flawless. There was no boot screen of course, but the boot was noticeably faster than my previously unflashed Nvidia 980ti seemed to do.

I went into familiar apps and games and the card was much quicker and smoother. In my X Plane flight sim, I saw NO improvement in FPS but that was on a third party add on aircraft which is a known resource hog. The next version of this flight sim will have Vulcan architecture and the X-Plane community universally believes that we will see an out of the box 30% FPS improvement.

Thanks for the inside info on the coming OS upgrades. I never liked it, but I have become accustomed to the planned obsolesce built into this technology. I’ll cross that bridge when I come to it. Remember, we suffered through the demise of System 9, Power PC, chipset changes and more. And we’re still here, albeit a bit poorer.

Today I will install my old 5770 just below the 580 in a second 16x slot. Of course I will power it off of my external power supply if I can find the right 6-pin adapter in my jumble of wires. I really don’t expect this configuration to work but my curiosity is getting the better of me. But no, I’m not buying yet another card for this set up, the 580 by itself will cover me as necessary.

My next upgrade fantasy will be to go to a Samsung SSD in place of my spinning boot drive. And I will also fool with learning how to flash this card which apparently, is not that difficult from what I’ve read here and in other forums. Thanks for the help.

 

[MIKX]

FlyingFortress.

You neglected to tell us which BRAND & details of your RX580 you have.

Sapphire ? Gigabyte ? XFX ?

8gb. ? 4gb ?

etc.

 

[FlyingFortress]

FlyingFortress.

You neglected to tell us which BRAND & details of your RX580 you have.

Sapphire ? Gigabyte ? XFX ?

8gb. ? 4gb ?

etc.

Sorry, It’s an unflashed Radeon Pulse Sapphire 8 GB for about $180 on Amazon. This version and brand of the card was mentioned numerous times in my research as being the most 5,1 Mac Pro friendly.

 

[MIKX]

Yes, the RX580 8gb is a great card. I have an MSI Armor RX580 8gb but I power it using . . ..

1. TWO x Mini 6pn to ONE x 8pin power cable.

Dual Mini 6 Pin to 8 Pin PCI Express Video Card Power Adapter Cable

Features: Dual Mini 6 Pin to 8 Pin PCI-e cable is to connect a PCIe video graphics card with 8 pin port to Mac motherboard with mini 6 pin port; Specification: Cable Length: 15-inches/(38cm) ; Connector 1: standard GPU 8 Pin male ; Connector 2 : 2x mini 6 pin male ( not standard 6 pin male); Gaug...

www.amazon.com

I connect the above cable to an EVGa PowerLink

EVGA PowerLink with AMD GPUs

Just got the EVGA PowerLink working with my Sapphire Dual-X 7970 3gb. IMPORTANT : The power input sockets on the PowerLink are 2 X 8 Pin female and cannot be changed. The EVGA PowerLink ensures that exact power demanded by a GPU is supplied. That said, one must still supply enough power to...

forums.macrumors.com

 

[FlyingFortress]

Thank you, MIKX. And I just added my old 5770 card to the other 16x slot and it works as a boot screen on this third monitor. I went into games and apps an no effect on FPS so far. Everything looks (strangely) NORMAL. And this gives me the additional headroom to run my flight sim on my other 2 monitors. My 5770 is plugged into an external COOLER MASTER V-550 which I needed to power my old GTX980ti (6 GB). I will stay with HS 10.13.6 (17G13035) as long as I can. But experience tells me that I will have to live with this for a while because anything can happen. In fact, WAIT, what? I just noticed that on the furthest left monitor some windows "window shade" on their own when open or dragged to that monitor. I've got to run out, but when I get back I'll change out that cable from HDMI to DVI-1 to DVI to DVI. I will probably have to order some DVI-D cables and reset P RAM. If it continues to be glitchy, I'll just remove the 5770...

 

[FlyingFortress]

Thank you, MIKX. And I just added my old 5770 card to the other 16x slot and it works as a boot screen on this third monitor. I went into games and apps an no effect on FPS so far. Everything looks (strangely) NORMAL. And this gives me the additional headroom to run my flight sim on my other 2 monitors. My 5770 is plugged into an external COOLER MASTER V-550 which I needed to power my old GTX980ti (6 GB). I will stay with HS 10.13.6 (17G13035) as long as I can. But experience tells me that I will have to live with this for a while because anything can happen. In fact, WAIT, what? I just noticed that on the furthest left monitor some windows "window shade" on their own when open or dragged to that monitor. I've got to run out, but when I get back I'll change out that cable from HDMI to DVI-1 to DVI to DVI. I will probably have to order some DVI-D cables and reset P RAM. If it continues to be glitchy, I'll just remove the 5770...

Right, too glitchy. As was said here in other threads MACs just don’t like 2 cards with different specs mounted on the same motherboard. I removed the card and put it back up on my spare parts shelf.

 

[vonfeffer]

Yes, the RX580 8gb is a great card. I have an MSI Armor RX580 8gb but I power it using . . ..

1. TWO x Mini 6pn to ONE x 8pin power cable.

Dual Mini 6 Pin to 8 Pin PCI Express Video Card Power Adapter Cable

Features: Dual Mini 6 Pin to 8 Pin PCI-e cable is to connect a PCIe video graphics card with 8 pin port to Mac motherboard with mini 6 pin port; Specification: Cable Length: 15-inches/(38cm) ; Connector 1: standard GPU 8 Pin male ; Connector 2 : 2x mini 6 pin male ( not standard 6 pin male); Gaug...

www.amazon.com

I connect the above cable to an EVGa PowerLink

EVGA PowerLink with AMD GPUs

Just got the EVGA PowerLink working with my Sapphire Dual-X 7970 3gb. IMPORTANT : The power input sockets on the PowerLink are 2 X 8 Pin female and cannot be changed. The EVGA PowerLink ensures that exact power demanded by a GPU is supplied. That said, one must still supply enough power to...

forums.macrumors.com

Hello MIKX!

I too have a Sapphire 7970 HD Dual-X 3GB RAM and am looking to flash its rom with a mac version but the information on how to do it properly and enjoy its full power seems to be a little confusing, do you think you could share your ROM with me, so I can flash mine?

Tks in advance!

 

[MIKX]

Hello MIKX!

I too have a Sapphire 7970 HD Dual-X 3GB RAM and am looking to flash its rom with a mac version but the information on how to do it properly and enjoy its full power seems to be a little confusing, do you think you could share your ROM with me, so I can flash mine?

Tks in advance!

Send a "PM" ( private message ) to me please.