ScreenBeam Bonded MoCA 2.5 Network Adapter for Highest Speed Internet, Ethernet Over Coax - Starter Kit (Model: ECB7250K02)

If there are two RP-SMA connections you can just get an extension like this otherwise you would need to get something like this. If you can't or don't want to occupy a PCIe slot with a wifi adapter your other option is do a wifi repeater closer to the desktop. As others have said hard line is better, would either a powerline or MoCA be an option? The SATA cable is probably just an extra accessory cable that came with the motherboard so if you ever wanted to plug in more hard drives you have the cable.

I'm using that to my sons bedroom. They put coax cable in every room but not RJ45 Ethernet. I bought this one and have 1GB Spectrum and it does in fact Speed test at ~975Mb+ https://www.amazon.com/dp/B08ML1TSXC?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1&th=1

Coax MOCA adapters can go up to 2.5 Gbps, like these ScreenBeams. Speed will vary depending on quality of copper cable, distance run and if you use the “encryption” for security, but you can ignore that encryption option if you are doing end to end termination of the coax, and don’t have any splitters that are connected to an exteriors service hook up. ScreenBeam Bonded MoCA 2.5... https://www.amazon.com/dp/B08ML1TSXC? ref=ppx_pop_mob_ap_share If you do have cable service for tv or as a backup to your fiber, then make sure you have a filter on that line. Filter, MoCA POE for Cable TV &... https://www.amazon.com/dp/B00KO5KHSQ?ref=ppx_pop_mob_ap_share