I don't think there are any 1GB parts. My guess is that it should be something like
"driver supports 400Gb, 200Gb, 50Gb and 10Gb Ethernet adapters"

I changed it to 10. Chelsio says 1/10/25/40/50/100/200/400GbE, but honestly, that's still not verbose enough for "find in Page" to work, it would need to be 1Gb / 10Gb / 25Gb / 40Gb / 50Gb / 100Gb / 200Gb / 400Gb, but I think that's just too much text.

Bleh, I guess you can use 1GB transceivers. (There was a T4 quad-port 1GB-only NIC with RJ45 that I'm thinking of in terms of 1GB parts, the T404). However, those transceivers would also work on older parts but aren't listed for, e.g. T6. My suggested list was based on the part numbers. The first two digits tend to be the ASIC and number of ports and the remaining digits are the top speed of said ports (e.g.[TS]<A><P><speed> is the rough format, but the 'xx04' are quad-port 1GB-only parts). The other entries in this page tend to focus on the top speed of those ports (e.g. the T6 entry below only mentions 100 and 25G though you can use 10G and 25G transceivers with, eg. the T6225).

That is why I only focused on the top speeds given at the end of the product name: 400, 200, 50, and 10.

This should be T72200-FH.

These names in the man page have historically matched the board's VPD's ident (pciconf -lV) and it would be great to keep it that way for T7. The official name for this board is T72200-FH and I need to dig up the exact names and variants of the other boards.