... and no, I don't think my specific issue has been discussed here already (but I may have missed it). 
I just set this up yesterday, and used the 2.5Gb "WAN/LAN" to connect my cable modem - all is good, and the WAN download speed may or may not be up from my trusty AX88U of 6 years.
BUT, I also connected the 10Gb "WAN/LAN" to my Windows 11 box as its connection to the world, and my Gigabyte mobo has a 10Gb Marvell AQtion 10GBASE-T on-board, and the [latest] Windows 11 driver for it has "Auto" link speed negotiation set... unfortunately, I am only seeing this as a 2.5Gb connection when I look at from the Windows 11 side.
Is there some way I haven't found to tell the BE88U that I really want it to use this as a 10Gb LAN link? I don't think that the link speed is being limited by the on-board Marvell chip, but I don't know.
However, it does look like my BE88U (running the latest Merlin version 3006.102.3) is confused about what the status of the "10Gb WAN/LAN" port actually is:
... note the WHITE "unplugged" coloring on this port - which is definitely in use, and talking to my 'puter - but only @ 2.5Gb.
Any ideas, comments, suggestions?
Alternatively, and assuming that the Marvell chip is not what is limiting me, could I possibly use the other10Gb port, what is it, "SFP"(?), with an adapter back to ethernet?
Thanks!

I just set this up yesterday, and used the 2.5Gb "WAN/LAN" to connect my cable modem - all is good, and the WAN download speed may or may not be up from my trusty AX88U of 6 years.
BUT, I also connected the 10Gb "WAN/LAN" to my Windows 11 box as its connection to the world, and my Gigabyte mobo has a 10Gb Marvell AQtion 10GBASE-T on-board, and the [latest] Windows 11 driver for it has "Auto" link speed negotiation set... unfortunately, I am only seeing this as a 2.5Gb connection when I look at from the Windows 11 side.

Is there some way I haven't found to tell the BE88U that I really want it to use this as a 10Gb LAN link? I don't think that the link speed is being limited by the on-board Marvell chip, but I don't know.
However, it does look like my BE88U (running the latest Merlin version 3006.102.3) is confused about what the status of the "10Gb WAN/LAN" port actually is:
... note the WHITE "unplugged" coloring on this port - which is definitely in use, and talking to my 'puter - but only @ 2.5Gb.
Any ideas, comments, suggestions?

Alternatively, and assuming that the Marvell chip is not what is limiting me, could I possibly use the other10Gb port, what is it, "SFP"(?), with an adapter back to ethernet?
Thanks!