Having two different types of GPU to run two monitors is possible, however, it may cause driver conflict, VRAM distribution stress, and other hardware difficulties.
2 Different Video Cards 2 Monitors
If you have a video card that has two or more of the same connection type (let’s say HDMI port) it can support dual monitors. Cards having two or more different port types can be interchanged with adapters to support dual-screen setups. Graphics cards with only one video port, won’t support a dual-monitor setup without adding a second card. Now the question is, should you do it?
If you have two different graphics cards with different power usage, memory, VRAM, and other specifications, you may face driver conflict, VRAM (Video Random-Access Memory) distribution stress, power usage issues, and other hardware difficulties.
Windows have a built-in system for dynamically moving loads between GPUs. Designed to move loads between an iGPU and a dGPU, while it sees the iGPU as a “Low Power GPU” and the dGPU as a “High Power GPU”. Both are used dynamically as appropriate. Even with 2 dGPUs, this doesn’t work. GPU 0 works as “High Power” and “Low Power” GPU, with no options for changing it.
Using both monitors with split mode, both of the GPU will be used to render and divide the video memory which will cause significant degradation in FPS and overall performance, which can be problematic.
You can use SLI or crossfire configuration you can use two graphics cards with one desktop, but is it worth it? Well, it does not degrade the performance, rather having two GPUs with 2 GB memory is obviously better than one with 2 GB memory. But, having a single 4GB memory is the best option. It depends a lot on your specifications, and whether you’re splitting the video memory or not.
Bottom line is, that you can go for 2 different video cards for 2 monitors only if you have a spare video card and got no other option. It’s always a better choice to get a video card with a higher specification to run a dual monitor setup, rather than having two different cards for two monitors.