Getting 4 monitors working with 2 GEFORCE GT 1030

I've just got my first build running Linux 18.3 on an ASRock Taichi X370 with a Ryzen 1700 CPU. I bought 2 GEFORCE GT 1030 GPUs to power 3 or 4 monitors, and mounted them in PCIE2 and PCIE3. Unfortunately, only the HDMI and DVI-D ports on the GPU mounted in PCIE2 work. A friend who works in IT tells me that the 2nd GPU simply adds graphics power to the first one, and that it cannot be used independently. Is there no way that I can power 3 or 4 monitors using these cards? I like the cards' passive cooling, and would like to keep them. Any help in getting both working would be GREATLY appreciated.

Thanks for your response. My Linux flavor is Mint 18.3 (Cinnamon-Sylvia). As best I can tell, running lshw only gives me information about the ASRock motherboard. Running "inxi -Fxzr" from the terminal does indicate that the Linux OS finds the two GPUs, however. Here is the relevant section of the output:
Graphics:     Card-1: NVIDIA Device 1d01 bus-ID: 2d:00.0
     Card-2: NVIDIA Device 1d01 bus-ID: 2e:00.0
     Display Server: X.Org 1.18.4 drivers: nvidia,nouveau (unloaded: fbdev,vesa)
     Resolution: 1920x1080@60.00hz, 1920x1080@60.00hz
     GLX Renderer: GeForce GT 1030/PCIe/SSE2
     GLX Version: 4.5.0 NVIDIA 384.130 Direct Rendering: Yes
I'm happy to post my question in another forum. Yet is there more assistance that I might receive here before I move on? Any help would be greatly appreciated.

The biggest effect of using two GT 1030s is less money in your wallet. As I said in my previous post, SLI is not officially supported and even if it was, SLI is a poorer option than getting a GTX 1050 or an RX 560 (which should cost about the same as two GT 1030s). Then there's also the fact that NVidia sells the GT 1030 with GDDR5 memory and DDR4 memory and the DDR4 version has roughly half the performance of the GDDR5 version, so you really have to be careful when buying a GT 1030 in the first place.

Actually you have been VERY helpful, PetrolHead. The key question in my post was whether or not my difficulty in getting 2 monitors working was a hardware issue. Your initial suggestion was that it was more likely a driver problem. Running "inxi -Fxzr" demonstrated that the hardware (as well as Mint 18.3) recognized both GT 1030 GPUs. Today I was able to confirm that getting multiple monitors working on the two GPUs can (in principle) be done via modifications in xorg.conf--my NVIDIA driver?™s configuration file. The NVIDIA driver (version 384.130) that came with my 18.3 installation provides a GUI called, ?œNVIDIA X Server Settings?? Using it with 3 monitors powered up, I did the following:

Click on "X Server Display Configuration"
Note that Display 3 is "(Disabled)"
Select the disabled display by clicking on it.
In the drop-down menu to the right of "Configuration:" select "New X Screen (requires X restart)"
Save changes as /etc/X11/xorg.conf

Now comes the part where my ?œin principle??hedge comes in:

Upon rebooting the system, Cinnamon (i.e., Mint 18.3) crashed. Continuing despite the crash, cursor movements were (for the first time) being displayed on my 3rd monitor. That's the good news. The bad news is that the crash left Mint?™s panel no longer functioning (and more problems that I did not bother to explore). Renaming xorg.conf restored the computer?™s previous functioning, leaving me to conclude that it is possible to get 4 GT 1030s running on Mint 18.3 installed on an ASRock Taichi X370. My first step in that direction will be updating my NVIDIA driver (www.nvidia.com/Download/index.aspx?lang=en-us).

By the way, I agree with you that two GT 1030s do not provide much performance-for-the-buck. But they?™re silent (no fan), which was the appeal for me. Besides, I?™ve already bought them and (fortunately) they are both the GDDR5 version. When I work out a way to get them both driving more than 2 monitors (without crashing the OS), I?™ll post it on forums.geforce.com.

Thanks again for sticking with me on this!

In January I promised that I would eventually post my solution on forums.geforce.com. Instead, its (re)solution is [URL=https://devtalk.nvidia.com/default/topic/1049968/linux/3-monitors-on-2-gt-1030-gpus-/post/5329642]here[/URL]) on nvidia's support site. The bottom line is that multiple monitors often cannot be driven by multiple GeForce GPUs. Unfortunate for me, this is the case with my pair of GT 1030s. If you want to power between 2 and 4 monitors, the best solution is to find a single GPU with that many monitor-ports--something that PetrolHead suggested initially. You will need multiple GPUs for more than 4 monitors. Given my primary interest in silence (i.e., passive cooling), I have opted for a single GeForce GTX 1050 Ti. That means that I have to settle for 3 monitors. But that's okay: Silence is golden.