Logging Disconnects For Specific Device?

I've been having random disconnects and extreme slow-downs on my primary computer that I'm trying to diagnose. Based on some prior narrowing-down, I suspect it's either the computer's ethernet network card or the 10g netgear switch I have it plugged into. (This is because when I connect with WiFi, where the AP is connected to a different switch, there are no issues).

I planned to diagnose the old fashioned way and wait for another disconnect/slowdown and then switch the connection to another switch to see if that fixes it. But this all happens just infrequent enough (maybe once a day while I'm actually at the computer) where it might be worth finding a more elegant way to monitor it.

So TL;DR: Is there a way, or what would be the best way to keep track of disconnects or obvious disruptions occurring for a single device?

Current Thinking: I'm going to try looking at the Sessions or Sessions Per Minute graphs and filter it for the specific computer, then look for any obvious dips/cutouts. Is there any way to monitor actual failed connections somehow though? (As opposed to looking for an absence of connections?)

Look for errors on RX or TX in the network interface status page https://<lan ip>/admin/index.do#config/network/interfaces