My Optiplex is a mini tower which is the largest size. I found this available locally:
MSI NVIDIA GeForce GTX 1650 Ventus XS Overclocked Dual-Fan 4GB GDDR6 PCIe Graphics Card
The overclocked part scares me. Overheating comes to mind. It has 4 GB RAM versus 8 GB on other cards. But the price is right at $260. And my power supply barely matches the requirements. If I do need a heftier power supply, it should be one with ether than average EMI characteristics.
It's looking like SDR-C needs at least at lower end gaming machine!
de Steve N6VL