Is adding second GPU card worth speeding up Final Cut Pro?

[mkary]

My configuration is the following:

CPU: i9-9900 k - Overclocked to 4.9 GHZ
Ram: 64 GB
GPU: Powercolor 6800 xt
Motherboard: Aorus Z390 master
SSD: Samsung 970 Evo Plus
Cooling: Noctua Nh-d15
Power Supply: FRACTAL DESIGN ION+ 860P 860W FD-PSU-IONP-860P-BK-EU

This post can be a continuation of my previous old post: https://www.tonymacx86.com/threads/final-cut-pro-optimizations.319971/

I'm a professional Final Cut Pro editor and I always try to speed up my working processes.

Therefore I'm considering of adding another GPU card but I'm not quite sure if this investment would be worth, because I would also need to change my power supply.

The working process is very fast especially when I compare it with my M1 Mini which I have in the office, but there's still space of improvement when adding elements in my timeline, especially 4k compressed videos.

So my questions is "Is it worthy? Has anyone tried it and what are the cons and benefits?"

Is it also easy to adjust the configuration with two cards?

Looking forward to any recommendations.

 

[Feartech]

My configuration is the following:

CPU: i9-9900 k - Overclocked to 4.9 GHZ
Ram: 64 GB
GPU: Powercolor 6800 xt
Motherboard: Aorus Z390 master
SSD: Samsung 970 Evo Plus
Cooling: Noctua Nh-d15
Power Supply: FRACTAL DESIGN ION+ 860P 860W FD-PSU-IONP-860P-BK-EU

This post can be a continuation of my previous old post: https://www.tonymacx86.com/threads/final-cut-pro-optimizations.319971/

I'm a professional Final Cut Pro editor and I always try to speed up my working processes.

Therefore I'm considering of adding another GPU card but I'm not quite sure if this investment would be worth, because I would also need to change my power supply.

The working process is very fast especially when I compare it with my M1 Mini which I have in the office, but there's still space of improvement when adding elements in my timeline, especially 4k compressed videos.

So my questions is "Is it worthy? Has anyone tried it and what are the cons and benefits?"

Is it also easy to adjust the configuration with two cards?

Looking forward to any recommendations.

possible that both cards needs to be the same make and model for any real benefit

 

[Edhawk]

Adding a second dGPU doesn't usually give you twice the graphics processing, because macOS is not set to work in that way, especially on a Hack.

You would probably see a maximum of 50-60% increase in graphics performance, as the 2nd full length PCIe slot on your motherboard will only work at x8 speed, and may well bring your PCIe x16 slot down to the same speed.

From your Motherboard's Specification page:

1. 1 x PCI Express x16 slot, running at x16 (PCIEX16)
   * For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.
2. 1 x PCI Express x16 slot, running at x8 (PCIEX8)
   * The PCIEX8 slot shares bandwidth with the PCIEX16 slot. When the PCIEX8 slot is populated, the PCIEX16 slot operates at up to x8 mode.

You are also reliant on the application being able to make use of the additional processing power from the second dGPU. If you think that will be a sufficient increase then install the second dGPU. I would recommend you install an identical dGPU as you currently own, to mitigate any possible issues.

As you are talking about a work system, you can probably claim the cost of the second dGPU and new PSU on your Tax return (I know I would and have done so in the past). So the costs will be somewhat mitigated against your company/Self-Employment taxable expenditure.

 

[mkary]

possible that both cards needs to be the same make and model for any real benefit

Yes, I'm considering to be the same.

 

[mkary]

Adding a second dGPU doesn't usually give you twice the graphics processing, because macOS is not set to work in that way, especially on a Hack.

You would probably see a maximum of 50-60% increase in graphics performance, as the 2nd full length PCIe slot on your motherboard will only work at x8 speed, and may well bring your PCIe x16 slot down to the same speed.

From your Motherboard's Specification page:

1. 1 x PCI Express x16 slot, running at x16 (PCIEX16)
   * For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.
2. 1 x PCI Express x16 slot, running at x8 (PCIEX8)
   * The PCIEX8 slot shares bandwidth with the PCIEX16 slot. When the PCIEX8 slot is populated, the PCIEX16 slot operates at up to x8 mode.

You are also reliant on the application being able to make use of the additional processing power from the second dGPU. If you think that will be a sufficient increase then install the second dGPU. I would recommend you install an identical dGPU as you currently own, to mitigate any possible issues.

As you are talking about a work system, you can probably claim the cost of the second dGPU and new PSU on your Tax return (I know I would and have done so in the past). So the costs will be somewhat mitigated against your company/Self-Employment taxable expenditure.

So in a few words it is not worthy.

I would be happy if someone with two cards and Final Cut Pro experience also comment but we will see if that even happen

I'm not sure if adding another GPU will increase my work process or will only decrease the render time.

 

[Edhawk]

You are using a Desktop class motherboard for a Workstation work process, so there are bound to be some compromises and limitations on what is possible on the Desktop motherboard.

The reduced PCIe slot speed and throughput being one of them in this case.

Using a Workstation motherboard such as an X299 would reduce this PCIe slot limitation, as they have multiple x16 slots that work at x16 speed. But they are a lot more difficult to get working with macOS compared to the Coffee Lake Desktop hack you are currently using.

You are correct, having someone with experience of using dual GPU's in a Coffee Lake Hack running FCPX would be ideal. But as you say this is not likely to occur. As most people only come here to find a solution to an issue, not to offer information about their work practices and experience using their hack in the real world. Which is a sad indictment really.

 

[Bustycat]

You are correct, having someone with experience of using dual GPU's in a Coffee Lake Hack running FCPX would be ideal. But as you say this is not likely to occur. As most people only come here to find a solution to an issue, not to offer information about their work practices and experience using their hack in the real world. Which is a sad indictment really.

Just simply not practical I think, even for desktop PCs.

 

[m4rk0]

So my questions is "Is it worthy? Has anyone tried it and what are the cons and benefits?"

I am not able to answer but I remember a couple of posts, for example this one. Check also GDS, he says he runs two 6900 XTs; they might give you some hints

 

[Barryjp]

So my questions is "Is it worthy? Has anyone tried it and what are the cons and benefits?"

Is it also easy to adjust the configuration with two cards?

I bought six cards very cheaply from an ex-miner, so I took the opportunity to build a dual GPU hackintosh. In my case I'm using Polaris RX 580 8GB cards and a 10th gen CPU but I expect the results would be similar with Navi cards.

With Final Cut Pro 10.6.6, editing C4K h.264 footage shot on a FujiFilm X-T4 at 200Mbps, the speed increase when rendering effects and exporting is about 20-30% when using two cards compared to a single card.

DaVinci Resolve seems to make much more efficient use of the additional GPU, with two cards being 80-90% faster than a single card when rendering and exporting.

The two cards don't need to be the same brand but they should be the same model, as using two cards with vastly different performance is actually slower than a single card. I tried putting an RX 460 in the second slot with an RX 580 in the primary slot and it was actually slower than an RX 580 on its own. I don't know the reason for this but perhaps it's trying to spread the workload evenly across both cards and so the 580 is constantly waiting for the 460 to catch up.

So, if you're using FCP, I'd say that a second GPU isn't worth it, but if you're using DaVinci then I'd say it is. Although, it depends on how much you pay for the cards.

 

[scottkendall]

perhaps it's trying to spread the workload evenly across both cards

This is pretty much exactly what it is doing, Mac OS load balances between the two cards. But the software also has to support working over both cards. Using two cards in Mac OS is not like using two cards in windows, where they act as one card. In Mac OS the software and the OS try to spread the load over as many cards as it can.