MP 1,1-5,1 GPU upgrade on Mac Pro 3,1

[jonow]

Newbie here trying to get a 2008 Mac Pro 3,1 running Mojave (thanks to dosdude) to run Photoshop 2021 and Capture One 2021 (both needing SSE4.2) for stills photography editing.

2 x 2.8Ghz Quad core Intel Xeon
32gb Ram
Mojave 10.14.6
Nvidia Geforce 8800GT 512mb (to be upgraded)

I’m hoping the final step is to update the GPU. From what I’ve read elsewhere in these forums it sounds like an Nvidia Geforce GTX 680 (mac edition) or GTX 770 (mac edition) will work out of the box as a straight swap - and give me metal support and a boot screen (my tech knowledge doesn’t extend much further than this & I don’t have windows for flashing….). My question is - will this then enable me to run PS21?? Just wanted to know before I pay up for a GPU…

I did have an issue after I updated to Mojave that no videos would run cleanly - so I added Dosdude’s Legacy Video patch - and all works fine now. As the Legacy Video patch wasn’t initially one of the patches recommended by Dosdude for my mac I just wanted to check whether that change will affect anything when I install the new GPU as I’ve read somewhere that there could be issues? I‘ve got time machine backups prior to the Video patch which I could revert to if necessary…

 

[Dayo]

A Classic MacPro is not the best choice for a workflow that depends on Adobe CC and I presume the same applies to COne.

You can be sure Mojave support will be dropped soon, and in any case, the SSE4.2 spoofing is only partial and certain features already do not work because they are simply not supported by the CPUs in such units.

 

[jonow]

Thanks Dayo - maybe I should face this depressing reality! Was just hoping that I could get CC running and squeeze a few more years out of the setup even if I have to stay on older version software....

 

[jimmyclephane]

I'm in the middle of the same process (exactly same model of Mac Pro actually). I can't speak for Mojave support yet as I'm having issues with the patchers at the moment but I can confirm that I have just upgraded to a GTX 680 and it worked straight away without any issues. I did have to make sure it was flashed for Mac and I needed to get a 6-to-8 PCIe Power adapter for it ... but other than that it was a very simple swap out from my Radeon HD 5870.

 

[jonow]

Thanks Jimmy - good to know about the 680. If it's any help - I tried many times to do an in-place upgrade to Mojave using dosdude's patch with no joy - it only worked when I formatted the drive.

 

[Dayo]

Thanks Dayo - maybe I should face this depressing reality! Was just hoping that I could get CC running and squeeze a few more years out of the setup even if I have to stay on older version software....

You can certainly run Mojave on a 3,1 without issue and can use Adobe CC 21 with some additional hacks. Possibly still with some limitations.

You should look into OpenCore for running newer Mac OS on unsupported Macs.

First install a supported Mac version (El Capitan or older) with your 8800 in place, use MyBootMgr (see my sig) to set Opencore up and then install Mojave directly. You will need something like a 680 or RX 580 to install Mojave.

Since you already have DosDude Mojave, you can just use MyBootMgr to install OpenCore. Just make sure you have always have a natively supported Mac OS version also installed whenever using an unsupported version.

GT 680 and RX 580 are good GPU choices. I prefer RX 580 myself as works out of the box and does not need flashing as the GT 680 does. You just have a black screen until the login screen.

MyBootMgr will give a bootscreen but works without as described.

 

[jonow]

Thanks Dayo - read through some of the Opencore/MyBootMgr posts on the forum and it seemed a bit beyond me but I'll reread the post in your sig link...

 

[jonow]

ps Dayo - what would your advice be with Opencore - is it more straightforward to start as I am now in Mojave or better to restore back to the natively supported El Cap and proceed (remember i don't have a GPU upgrade yet)??

 

[Dayo]

You can continue from Mojave since you already have this. Your legacy GPU should be able to run this. Not at top performance, but able to access this.

You do need to separately have a natively supported Mac OS version available to allow accessing your Mac. That is, avoid situations were an unsupported version is all you have available. Not overwriting the unsupported instance but a separate supported one.