All the marketing material says this device is only 10/100Mbit, so one would assume it is just that speed. However, when I opened the User Guide (http://routerboard.com/pdf/357/rb751U-2HnD-ug.pdf), on page 7 under "Connector Index" section it says "RJ45 Gigabit Ethernet 100Base-T ports, Ether1 accepts passive PoE power".

Also, when I open up Webfig on my unit and select Interfaces -> ether2-master-local (or any of the ethernet ports), under the Speed section the options are 10Mbps, 100Mbps and 1Gbps. 100Mbps is selected by default.

I haven't tried switching it to 1Gbps for fear that it may ruin the hardware somehow (not sure if that's possible). Has anyone else experimented with this or know for certain whether it's just 10/100 or if it's also 1Gbps capable too?

"on page 7 under "Connector Index" section it says "RJ45 Gigabit Ethernet 100Base-T ports"

It has been mistyped.

"Also, when I open up Webfig on my unit and select Interfaces -> ether2-master-local (or any of the ethernet ports), under the Speed section the options are 10Mbps, 100Mbps and 1Gbps. 100Mbps is selected by default."

Because the RouterOS can handle the Gbps speed also. It will only work at maximum 100Mbps.

"I haven't tried switching it to 1Gbps for fear that it may ruin the hardware somehow (not sure if that's possible)"

Probably nothing will happen. The switch IC can handle maximum 100Mbps, so you cannot make it "work faster". It's similar when you type in the command line: beep
The integrated speaker should beep then, but because RB751U does not have one, nothing will happen.

Ok, thanks for the reply! Knew it had to be too good to be true.

Ok, thanks for the reply! Knew it had to be too good to be true.

I believe there is a gigabit version coming out soon, that is probably why the manual mentioned it.