Cooltrader i don't think you'll see any difference using dual processors - i run Realtick, IB and a mirc program all on one machine using Windows XP, plus open browser, Microsoft Excel - never bogs down - and I have an Athlon 850 with 512 Ram. As far as multiple machines on a single DSL/Cable, just purchase a DSL/Cable Router - about $80 at any Circuit City/Best Buy/Comp USA store - they're made by Linksys or Netgear, among others, and easy to hook up - just need a NIC in each PC.