You can try an update of the modem software from the manufactures site or if that fails, then a new modem will be needed. I think from the model number you give, this modem is not compatible with XP. j.
It looks like you should be looking at the motherboard site for AMR drivers as that appears to be what you have got the AMR drivers are on the Motherboard CD for the AMR port and it will not work until you load these. It may be a good idea to try them first