Bought a house, want to run cat6 cable..

[badass]

If you're using shielded cabling, it has to be grounded properly - otherwise it might be making things worse!

Have you tried different nics at either end to see if it's definitely the cable that's struggling?

Common myth that one

https://www.cablinginstall.com/home/...reened-cabling

Shielded, ungrounded cable is better then unshielded cable by at least an order of magnitude. Grounding the shielding simply helps more.

Any way, I've completely ignored my own advice and gone for Cat 6a rather than Cat6 now my house is getting extended. All my old cables had to be cut

Cat6a cost me an extra £25 over Cat6 and the fact that I have access to large voids everywhere means bend radius isn't a concern to me. When I last checked a few years ago the price difference was much, much higher.

[ik9000]

I got u/ftp 6a bc2a LSOH (orange inflammable stuff) for a really good price so installed/am installing one of those and one purple cat6 utp LSOH to every socket (I'd got the cat6 in the loft already).

Edit: checking I see they now do f/ftp b2ca for £20 more per drum - I'd have gone for that if they'd offered it before. I wonder if they've put the prices up though, they look higher than I remember.

If you're running multiple cables to each socket I'd definitely recommend using different colour sheaths where possible to help you keep track. I have a tester that will ID cables for me, but it's a PITA if you can avoid it.