Intel Switch

We are using Intelexpress 510T Switch with stack & matrix interconnection. We hv 70 nodes (40 Dsktop & 30 thin client) 5 servers (2 NT 4 & 2 W2k Adv Server 1 Novell.). We hv forced all to 100mb & full duplex. Still our network is slow & also we get time out when pinging. Our network is in ECAT5 cable & is tested with Fluke meter. Also we checked all parameters & hints given by intel in their website. Can anyone give us some clues on the above.

Thanks