Netware Client causes slowdown

When we install the Intranetware Client (4.71) for NT onto our NT workstations (NT Sp 6a) we find that there is a dramatic slowdown in network access of the machine. For example it takes twice as long to copy a file from server don to PC. This happens even when you log into ‘Workstation only’ and access an NT server. What would configuring as a P-Node do (and how do I do it)? What problems will disabling the NWLink binding cause? Any other solution?