samba - May 1999 - Bad performance on samba server

I have installed a samba server (1.9.17p4 Linux 2.0.36 from redhat 5.0)
on a dual pentiumII 350 64Mram with two
ultra wide scsi disk drives on a 100Mbit port of a 16x10Mbit + 2x100Mbit
Allied Telesyn  switch  .The copying operations work at quite same speed
even I copy from Samba server or a Win9x Station  if I try to open a
Word doc from server it is much, much slower ( aprox 20 times slower
)that opening the same document from other Win9X station of the network
Where can be the problem ?

    Paul