My friend just brought a PS/2 mouse with roller. Because he was using a serial mouse before, he brought a adapter so that he can connect his new PS/2 mouse into the Serial Port. When he turn it on, the computer won't recoganize it. What could be the problem. Later, he found a PS/2 port. Let me back up a little. He is currently connecting 2 printers on his computer. One regular printer connected to the onboard Parallel port and the other one (Fax 3in1) is connected to a Add-on Parallel port PCI card. I think the PS/2 port came with the Parallel port PCI card. Now, his PS/2 mouse is working. But the computer is not recoganizing the Fax 3in1 machine. What could be wrong? I think it is because of the IRQ address. What do you think.