Some BIOS have a WAKE ON RING setting. Turn it off.
I'd tell a bit more, but no make or model was provided in your post.
Bob
I'm running Windows XP home and when the phone rings while the computer is off the computer comes back on. I believe it has something to do with the modom softV92 data fax modem. However am not sure. have not been able to find any reason for why it would happen and would appreciate any help

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