Can not surf wireless 'net while printing to USB printer

Computer is 510/E510, WinXP Home, 1Gb, no modifications (computer as from factory), wireless 'net via cable TV, USB connected H-P multi-function printer. Problem: while connected to internet, can not print. While printer turned on can not surf internet. Just turning printer off restores internet but computer re-start is required. Turning printer back on renders internet unavailable. Internet connection is via USB/wireless adapter; printer connection is via USB. Wireless adapter is plugged into rear of computer, printer is plugged into front but was originally plugged into rear. It seems to me there must be a conflict somewhere in the USB connection. Open Device Manager, no conflicts appear. Purchase new USB wireless adapter, install new software; no change. Printer is new, all software installed. Prior to printer purchase, internet worked OK. Thought about installing a wireless card to eliminate the USB wireless connection but haven't gone that direction yet.