Newbee Quest developer hardware questions

I have just recently purchased a new meta quest 2 256GB headset, and one of the things I wanted to do with it is to try my hand at developing software for it. But, I have a computer that is a bit older, although I feel it should be perfectly capable. I've done cad work on it with no problems. It is an HP 8300 Tower Computer, Quad Core i7 3770 upto 3.9GHz, 16GB Ram, 250GB SSD + 2TB HDD, 2GB GeForce GT710 4K Video Card. Been a little frustrated trying to get a development environment setup. No problems installing Unreal Engine 5, although it did complain a little about possible errors with my graphics card. It suggested that I update my driver, but the newer drivers do not support the GT710 card any more. Anyway, found out I need a link cable to hook up the headset to the PC, and I did go ahead and order one, even though the docs state that my card is not compatible. BUT, it also seems to infer that just because it's incompatible, it could still work? I guess I'll find out when I get it. I am certainly up for getting a better GPU, but herein lies my questions: My motherboard has a PCI Express x16, but I believe the PCI version is only 1.0? There are no PCI-e 1.0 cards out there that are supported either. I'm figuring I'll have to buy a new PC! But now I read that PCI-e slots are backward and forward compatible, so I should be able to plugin a PCI-e 3.0 or 4.0 card and it should still work. Any experts out there that can weigh in on this? Will it work? I'd rather spend my money on a better GPU than go thru the hassle of getting a new PC setup for this! Thanks in advance for any help you can offer!