Adding second graphics card ?

[CheekyGimp]

I just got a new rig and it has a Nvidia GeForce GTX 1080Ti 11GB GPU.

Which means that my current rig (GTX 980Ti) will now be used as a secondary rendering machine (if I have a backlog of renders, I'll move them over to this rig to run)
My question is: I have an old AMD Radeon 7800 GPU lying around at home and was just wondering would there be ANY benefit to slotting this into my "backup" rig. I know i couldn't use SLI, etc. but would it be useful to connect the AMD to the monitor (for basic display purposes) to allow the 980Ti to work solely on rendering ?
As you can probably tell I'm not a PC hobbyist (not used to building rigs, etc.), so apologies if this is a stupid question...

 

[Rich]

No, it's not a stupid question.

If you're both rendering and "displaying" from the 980Ti, the render will proceed somewhat more slowly. Makes sense, of course, since Windows uses the GPU for display purposes. So you will get some rendering performance improvement if you have your monitor connected to an alternate card.

Unfortunately, this won't gain you back any GPU memory in the 980Ti, afaik - there have been a long series of discussions on the Daz forums to the effect that Windows reserves memory on graphics cards that don't have monitors, "just in case" someone decides to plug in a monitor. But clearly adding the second card won't hurt.

 

[f95zoneuser463]

Obviously your situation is different with it being a secondary PC, but here is my experience:

Main system configured with GTX 760 card + Monitor only
-> PC was unusable while rendering! You can seriously watch your graphics card slowly paint the browser window, the mouse-cursor would freeze up and letters would appear 10-30 seconds after typing them because the GPU is to damn busy.

The same system:
primary GPU set to Intel HD graphics 3000 (i7 2600K CPU) + Monitor connected
secondary GTX 760 dedicated for rendering + no Monitor
-> Rendering in the background and working on the machine at the same time no problem at all!

I believe the AMD card cannot do i-ray ... don't know for sure since I'm on the green team atm.

 

[Rich]

You are correct that Daz/Iray cannot use to the AMD card to perform rendering functions. NVidia only.

 

[TheTalSet]

It seems that the only way is to hope that AMD or someone else is making a ProRender Plugin for DAZ3D

 

[OhWee]

So, in my latest computer rig (the laptop bricked itself), I have a Ryzen 2400G (has integrated Vega 11 Graphics) and a 1080 Ti.

As far as the system is concerned, all desktop (and gaming) functions are handled by the integrated Vega GPU, including the Daz viewport. I have my 4K monitor hooked up to the motherboard HDMI port.

The 1080 Ti is installed as well, but doesn't drive any monitors. Interestingly, I did note that Daz reported the full 11 GB of VRAM in Windows 10, so this may or may not have allowed me to avoid the 18% Windows VRAM tax for the 1080 Ti. I'm not sure on this, though. I did recently do a render with 8 characters on the 1080 Ti, and didn't hit a Ram wall. 5 characters was often the best I could hope for on my now bricked dual 1080 system. I'll probably do a more intense scene fairly soon with more characters, and I'll report back when I hit the 'VRAM wall'.

The Vega graphics run things just fine, and the Daz viewport has a very nice response rate with this setup. The refresh rate on the 4K monitor is rather low in my setup (29 Hz), but since I don't play shooter games (where the framerate is more important), that suits me just fine. I play mostly turn based and/or older games anyways...

So, short form, you could use the AMD card to drive everything else, and just use the Nvidia card for Daz. You may take a FPS hit in your gaming (the 980 Ti may or may not be faster in games) but priorities man!

Also, another thought if you have an extra PCIe-16 slot in your 1080 Ti system. You COULD put the 980 Ti in the same system. Daz will see it just fine, and will use both cards for rendering if you check the boxes for both cards. Even if the PCIe slot is running at only x8, you'll still see a dramatic speedup in render times with both cards. Currently, going from x8 PCIe to x16 PCIe will only gain you a couple of percentage points on your render times, so the x8 (even on both cards) isn't a big deal at all for rendering.

Of course, your scene size would then be limited by the 980 Ti's memory (6GB?), so for larger scenes you'd simply 'uncheck' the 980 Ti when rendering said scenes, if you combined the two cards (980 Ti + 1080 Ti) in the same system.

There are multiple benchmarks in the Daz Iray Benchmark thread on the Daz Forum that have people combining 9xx cards with 10xx cards for rendering, and even 20xx cards with either...

 

[TheTalSet]

I just made a request to AMD if there ever will be a plugin for DAZ3D. I am excited what they will say.