I possess a fresh ASUS TUF Gaming Z690-Plus WiFi D4 with LGA 1700 MB RAM, Intel 2.5GIG NIC, running Windows 10 and 11. The system displays only 1GB despite the hardware specs. After updating drivers from both ASUS and Intel, the problem persists. My Mellanox ConnectX-3 functions smoothly at 10Gbps but struggles with 2.5Gbps.
It will connect CAT6 to a 10Gbps switch over a brief distance of just a few feet.
Older 10 Gig switches aren't compatible with 2.5 or 5 Gig connections. Remember that 2.5 and 5 Gig represent a newer standard, meaning you'll need a more recent 10 Gig switch for possible compatibility.