dialup not working after ethernet removal

hi there, in anticipation of my cable modem hookup which happens in a week, i went ahead and installed a ethernet card(same kind as cable comp uses). everything installed fine, no confllicts etc...Not willing to leave well enuf alone,i removed the card,cleared it out of device manager etc. Upon trying my dial up modem to my ISP i instantly got the error message that my dial up connection could not be made,machine not communicatiing with modem. The 3com modem shows everything working fine,device manager says ok,but no dial out/dial tone. If i remove the dialup modem from device manager, reboot, Windows 98se detects new hardward, reinstalls the modem and i can dial out at that point and stay connected for the rest of the time im powered up. If i shut computer off,turn back on and try to connect to ISP, the error message happens again and i go thru process of reinstalling etc etc...Norton diagnostics for the modem indicates theres no communication fromthe Com port the modem is on..What did i do, something simple no doubt, sure would appreciate any tips. thankyou