Our 8/1MB internet connection first run 30 metres thru phone line and then was shared with 6-8 computers and up to 4 PS37x360s thru up to 3 routers and 25 meter CAT-5 cable (my connection was strauight from the box with 5 metre cable), so we were competing for bandwidth with each other.
Even when I took everyone out physically I could achieve 2.7/0.6MB speed at best (share that with others and you get the picture

)
So we decided to activate the second phone line which comes directly to my room.
It too has now 8/1MB connection, which I can connect even more directly to my computer and speed test cave result of 6.1/,07 MB
We have not yet moved the other DSL modem to downstairs so they can get shorter cables too (5 meter phone line with max 10 meter CAT-5 cables), but they too should get way faster connection.