The strong suit of gaming PCs is their GPU, because that’s a main part of what is required for playing games. For photogrammetry the processing relies on the CPU, RAM and hard drive in addition to the GPU and the setup needs to be balanced so that there is no bottleneck.
I found some interesting discussions on Quora on the comparison between gaming PCs and workstations:
- https://www.quora.com/If-you-had-a-high-end-gaming-PC-and-high-end-workstation-how-would-they-perform-if-they-were-doing-each-others-tasks
- https://www.quora.com/What-is-the-difference-between-a-workstation-and-a-gaming-pc
I do not have specific recommendations on the two computers, but I can recommend having a look at these discussions:
- Workstation comments: https://community.pix4d.com/t/3564
- Pix4D community hardware benchmark: https://community.pix4d.com/t/4079
- Quadro vs GeForce: https://community.pix4d.com/t/4284