i would
my family has a 600mhz celeron from 1999 or 2000
we had ours connected to usb (obviously, a slow one)
then my dad got a free ethernet card from sbc dsl when he got it for his office . . . that comp already had one, so we installed it into our home computer, and the speed from cable began to show its true form when we did that . . .
long story short . . . yes, do get an ethernet card - its the best solution for that
lol, i didnt know they had cable service in amish country! lol