I'm not clued up on the use of the filtered faceplates so I hope others will jump in, but my hunch is to filter as soon as possible at the master socket, if effect of this is to prevent any voice extensions from adding interference / noise to the line.
This sounds like (1) unless I have misread it.
On the gigabit switch, typically you can find a range of sizes - 5/8/10/16 ports - (and more for the rack-mounted kind).
The rule of thumb would be to think of all the things you have with ethernet and still have a few ports to spare.
However the thing to try first (once the gigabit NIC is fitted) would be to link the two computers together directly - not via the router - and check they link up at the expected speed, and try a few transfers.
Edit: Without the router to give out IPs it is acceptable to let them auto assign 169.254.x.y addresses as you can still network locally without having to manually set IPs. Don't worry about XPs "Limited or no connectivity" warning, it's a bit misleading as it just means no gateway found (router to the internet in this case).
If that works you can think about adding a switch, placed such that the router, computer and the downstairs end of the CAT5 run each connect to it, then the other computer at the other socket. The computers will still show a 1G link for LAN transfers while the connection to the router will be 100M without slowing down the 1G LAN.
Edit: This is assuming you were able to test all 8 pins were connected and in the right pairs (if the link falls back to 100M between floors it suggests a problem on any/all of pins 4/5/7/8)
In your setup there will be nothing connected to the 100M NIC in the XP computer, though having two NICs gives it the future option of going into "retirement" as a dedicated firewall.
I'll have a look around tomorrow on switches but for at 5 or 8-port for starters it does not need to be expensive.
prompt $P - Invalid drive specification - Abort, Retry, Fail? $G
prlzx on n e w n e t Max ADSL
Edited by prlzx (Sat 08-Oct-11 01:05:21)