Modem restarting PC

[Bana999]

Strange issue, when I use my dial up connection, it restarts my computer. It usually does it after the connection has been established, and restarts when some app tries to utilize it (web browser, online games, etc). The drivers are up to date, but don't know the modem type at the moment. Rest of system specs are as follows:

P4 650 series
2gb ddr2 ram
creative 7.1 24bit sound card
ati x1800 xt

rest is pretty standard, as is the modem itself. I doubt its some freaky power issue, as my PSU is more than capable of handling the system. Just want to see if anyone has had a similar problem before I go ahead and buy a new modem.

and for those wondering, i have high speed wireless, but the company that runs it thinks a 5 minute dhcp lease adds to network stability.

 

[ski]

Check for viruses and remove all spyware, if not previously done.
If no luck, then uninstall the modem drivers, remove the modem from Device Manager, shut down the system, reseat the modem, restart, let Windows recognize the modem, and reinstall the drivers.
If still no luck, then install the modem in a different slot.
If no good, then try a different modem.