Freezing Laptop on network

Having problems with a dell latitude cpt 466gt laptop with 64mb memory, win95b connected to a netware 4 network. It’s connected via dell’s port replicator. The user is reporting that the laptop is locking up for no reason. The user uses groupwise, the internet, and a dos-based program. User stated that programs are not being opened at same time. User locks up at least once a day. Desktop users not having this prob. User isn’t downloading anything from internet. I’ve made sure no virus programs were causing the prob, I checked the hardware acceleration and set to none. Made sure laptop wasn’t going to sleep,powersaver,etc. I don’t know what else to check. Someone, please help!!