Comment by simoncion

> It seems to be a mix of hardware bugs and a driver that doesn't properly account for them.

~~yaaaaay~~

Also, who the heck knows if my switches are behaving correctly? I may be dealing with a system with multiple failing components.

I'd never considered Mellanox hardware... I'd always thought of them as "super expensive datacenter hardware", but non-Infiniband cards I can see on Newegg aren't entirely-unreasonably priced. (TBD if I can find a PCI-E 2.0 1x card, though). I'd not heard of ASIX, and they have a card that would fit in my slot, but -sadly- no in-tree driver. It looks like the only in-tree driver is for a 100mbit card... the AX88796C.

Anyway, thanks for the advice/info and the mention of more-reliable manufacturers.