Hey all hows it going

ive asked on all the forums, and searched the net, and i cant find a way to change the network cards speed from 100mbps to 10mbps, is there any way to do it, as i think its what is causing my network card to go up and down...

im using a netgear fa-311 card, using the natsemi.o driver.

any form of help would be great

edit: also forgot to mention this is a hd-install of the knoppix 3.3 cd!