Advice on multiple a GPU setup with an Asus Prime Z370-A

[jimjamgraphics]

Hi all, I'm looking for some advice for a PC upgrade.

I recently used PCPartPicker to build a new work machine. A lot of my work involves Cinema 4D, X-Particles (physical simulations) and Octane (GPU) rendering, so I built it with that in mind. However, I also had an idea of expanding it to a more powerful, multiple GPU render machine. And that's where I'm hoping for some advice.

Here is my current work machine spec:

- Fractal Design Define R6 Black TG Midi Tower Black
- Asus Prime Z370-A
- 8th Gen Core i7-8700K
- 4 x Corsair 16GB DDR4 Vengeance LPX 3000MHz
- 1x GTX 1080ti - 11GB GDDR5X
- 1 x 1TB Samsung 970 EVO M.2 NVMe SSD
- PSU: Corsair CP-9020094-UK RM1000

I am considering buying another GTX 1080ti and I also have a GTX 1080 to throw into the mix. Eventually I'd like to have as many GPUs running on it as possible.

The first question I have is regarding the best way to configure any additional graphic cards, and avoid bottle-necking with things like PCIE bus speeds? I'm aware that the motherboard will run:

1 x PCIE Gen3 at 16x
2 x PCIE Gen3 at 8x
1 x PCIE Gen3 at 8x plus 2 x PCIE at 4x

What I'm less aware of and have found difficult to find an answers on line, are the following questions:

- Will PCIE Gen3 at 16x bottle-neck a GTX 1080ti? And how will bottle-necking effect GPU render times?
- If I want to go down the route of adding GPU cards with a PCIE riser, what limitations in terms of bottle-necking come in to play then?
- Would I be best in investing in a new motherboard and/or CPU to make sure I have more bus bandwidth? Are there any that you would recommend for my needs? If possible I'd like to avoid buying new CPU and RAM (will the CPU be a bottle-neck for me)

There appears to be a lot more detailed information on bit mining rigs, and whilst they are similar setups, I also gather that they have different performance requirements.

Any help will be massively appreciated, Thanks, Jamie

 

[King Dranzer]

One recommendation for you is to get the X299 build instead of Z370 as it has many features suitable for your workload and max GPU support without bandwidth compromise. Checkout ASUS WS SAGE X299 motherboard.

What is your max budget for the build.

 

[jimjamgraphics]

One recommendation for you is to get the X299 build instead of Z370 as it has many features suitable for your workload and max GPU support without bandwidth compromise. Checkout ASUS WS SAGE X299 motherboard.

What is your max budget for the build.

Thanks for tip King D. I'll investigate more into the X299 more.

In terms of budget I could probably just about stretch to getting the X299 with an Intel i9 7900X. That will mean I could just settle for running my 1080 and 1080ti for now and buy more GPU cards later on down the line, as and when they are justifiable.

It looks like the TUF X299 Mark 1 might be the way to go.

 

[King Dranzer]

TUF X299 does not support 4 GPUs(3GPUs max) and only supports 2GPUs with full x16 bandwidth. The SAGE X299 on the other hand supports 4GPUs with all the 4GPUs getting full bandwidth support. Not all software will perform better with x16 over x8 but the software which does will give great noticeable improvement in performance.

 

[jimjamgraphics]

TUF X299 does not support 4 GPUs(3GPUs max) and only supports 2GPUs with full x16 bandwidth. The SAGE X299 on the other hand supports 4GPUs with all the 4GPUs getting full bandwidth support. Not all software will perform better with x16 over x8 but the software which does will give great noticeable improvement in performance.

Thanks again for the advice. I really appreciate it. The SAGE looks pretty impressive and ideal for what I'm after.

So from what I can gather, a lot of Cinema 4D features are single-core (I'm yet to find out for definite if it uses multi-core for it's simulations). So do you think I will notice a performance hit if I go from having an i7-800K to an i9-7900X?

 

[King Dranzer]

If you go with i9-7900X over i7-8700K there will be minimal to no performance loss unless you compare the OC capabilities. If you consider OC capabilities as I expect you to OC the difference will 4-8%(10% in worst case) which is very small loss. But when working in areas which utilize multi-core performance there will be extremely huge gain.

Also check price of i9-7920X as it comes with extra 2cores and 4threads for minimal bump in price over i9-7900X.

 

[King Dranzer]

Yes SAGE X299 will suit your requirement perfectly.