i spent 20 staight hours trying a MULTITUDE of ways to get thismodem to work on my p233mmx system. this is the FIRST piece ofequipment I have failed to install in my 3 yrs of computing!!! the install cd is poor no install program' just a list of drivers...when i did finally get it recognized and installed{diagnostics SAID it was fine)the program that is SUPPOSED to allow you to change com port and irq only APPEARED to change these settings....in actuality they remained set at default from "install cd" DO NOT BUY this paperweight !!!its a poor PW also{too light LOL !}