Desktop Computer and RBR-50

RBR50 plus satellite, Firmware version: V2.7.4.24, Windows 11,

Summary of the problem: Every digital device in our house runs at awesome speed. My brand new Dell XPS 8950 desktop is connected wirelessly and runs at a very slow speed and bogs down.

This problem began several years ago. I have spoken with both Netgear and this forum several times about this problem. I had an older Dell with a service contract. Dell replaced motherboard and wireless card. Spectrum put in a new modem. No one's advice fixed it. One thing that made me extra crazy was that I took the computer to a repair shop and it connected at super fast speeds. But not when connected in my home to my Orbi.

I thought it was unfixable so I finally bought a new desktop- Dell XPS 8950 desktop. But a new computer did not fix the problem. It runs just as slow as the older computer.

I have an RBR50 and a satellite. Our ISP is Spectrum. We have a connected tv, multiple ROKU, 2 iphones and 2 ipads. I can see all those devices in the Orbi app and via the Netgear login on my desktop. Digital devices run over 200 mbps. My desktop runs at around 40 mbps using wireless.

A network engineer friend looked at my Orbi setup. He pointed out that within Orblogin.net under ATTACHED DEVICES my desktop computer shows a connection type of 2.4G where nearly everything else in the list has a 5G connection.

He went to Advanced/Wireless Settings and then under Advanced Wireless Settings (2.4GHZ) he unchecked Enable SSID Broadcast. But that did not fix it.

Is there a way to force my desktop to use the 5G? If I bought a new Orbi could I control how my desktop connects? If so, what Orbi could I buy that did not cost a fortune. We are a small household.

I have problem solved as much as I know how to do. Can you tell me anything else I can check?