Slow access through DOS

I have just installed a new Dell Dimension 4100/1.3 ghz PC and install Client 3.3. The PC logs into a Netware 5 server (DEll Powerdge 1300/500 mhz)that houses a DOS program. Access to this program from this new PC is very slow yet access from the older, slower PC’s that operate on the network is operating fast. Please advise, for I am at a loss.