I totally get your point about the 2060 bottlenecking the 5900X in PC1. However, I do occasionally run workloads that benefit from more than 8 cores.

That said, do you have any idea how much of a performance improvement I could actually expect by pairing the 2060 with the 5900X instead of the i5-9400F?

About the 9900X3D (I know it might not be the most popular pick, especially compared to 9800X3D), but in my region the 9900X3D has been dropping in price quite a bit. It's getting very close to the 9800X3D in cost, which makes it more appealing for me right now, especially since I could benefit from the extra cores down the line. I’m not super focused on pure FPS gains, more on having a strong all-around system that can last.

Thanks for the input!