I might have been lucky, but in the one home and one office were I've connected 10gbit switches and PCIe cards, it has just worked. Especially the office was a nice surprise, because it is at least 20 meters (probably more) of unknown cabling and at least one unknown patch panel between the utility closet where the NAS lives and the desk area. The cables were run 15 years ago, so I expected it to be cat 5, but clearly not.
It is nice moving/streaming large files across the network at 10 gbit. It really is ten times less waiting than with plain old gigabit.
Of course, most of the time I'm working with lots of small files and then the spinning disk array in the NAS has no chance to saturated the this giant pipe, or even a normal gigabit connection...
I know when I was doing some custom wiring in a house around 2005-6, it was clear that cat-6e was the thing to use if you wanted any future-proofing.
So I bought a reel of that even though I was only going to be using 1000-BaseT. I don't remember there being too much premium on the wire itself.
> The cables were run 15 years ago, so I expected it to be cat 5, but clearly not.
Did you check the jackets? I've got Cat5 (no e) marked cable running 10gbaseT. A lot of cable exceeds the specs on its jacket and specified wire provides enough signal to noise for the provided length in dense conduit. When you have shorter runs, without dense wiring, lesser cable can work.
Same. I ran CAT6 from one end of our house to the other, because my home office is in the opposite corner as the fiber coming in to the router. After running that, and manually crimping everything, it Just Worked from the first time I turned everything on. That felt pretty good.
> The cables were run 15 years ago, so I expected it to be cat 5
FWIW, Cat 5e supplanted Cat 5 25 years ago.