This doesn't sound like a known problem
PCMCIA on Toshiba laptops
Strange problem with a NE2000 card on Satellite 310CDS (Eric Buist)
Date: 2000, Aug 24
From: David Hinds <firstname.lastname@example.org>
Check your system log for error messages when the network stops. Also
check "ifconfig" to see if it is reporting any errors.
to: "This doesn't sound like a known problem"