I was about to say that you don't need a kickass Nvidia card to get started, learning the basics of DAZ... but then I looked up your GPU and was... amazed. A GPU from 2009 that is still running? that's actually cracked. You'll be able to register it as a vintage computing device soon...
Anyway, there's lots of ways to build a game, and you absolutely don't necessarily need to have high-res perfect 3d renders. One of my favourite 3d render games was done mainly on a laptop GTX1650 (
https://f95zone.to/threads/nothing-is-forever-v0-7-3-mrsilverlust.87506/). The gfx are simple and stark because the dev literally had to strip out the complex figure materials to get it to render, but the story and gameplay is incredible.
Unfortunately, I greatly doubt that a NV210 gpu is supported in Iray. You'd have to stick to making a text only game (or with placeholders which you will come back to fix later)
Eyecandy games have their place, but having "state of the art" renders is absolutely not the only thing that makes a game good or bad.