Tried to install a cheap modem in a PC last night and it either wouldn't get recongnized, or would not get a dial-tone, which there was. XP Home and there were drivers included with the modem. I have trouble troubleshooting modems because I don't understand the correlation between COM ports and the PCI slots. Also, oddly, when the modem was in 1 slot, it caused problems with the display settings, when it was in another it could not be recognized, but the display was fine. There is only 1 COM port showing in the list of ports, but there are 3 available PCI slots in the box. I'm going to get a costlier name-brand modem tonight just to see if that works, but I want to understand the problems. Can anyone clear up what, to me anyway, is a very foggy issue?