I had one of these and was able to use a Zoltrix brand model FMVSP56i3 ISA 
56k modem with no problems. They were still around about 6 months ago so 
you may still find one out there somewhere. The system requirements are:

System Requirements
IBM PC/386, 486, Pentium or faster compatible computer with the following:
·       One free 16-bit slot
·       One or more 3.5" floppy drives
·       MGA, CGA, EGA or VGA
·       4 MB RAM
·       Hard disk with at least 8 MB of free disk space
·       Optional Microsoft or compatible serial mouse
·       MS-DOS 3.3 or later and Windows 3.1 or Windows 95/98

You can see the specs at:
http://www.zoltix.com/products/fmvsp56i3.htm

(No not a typo, Zotix distributes ZolTrix products in US !!)

Good luck -  BTW it was less than $65 US!

Doug

At 7/28/00 09:37 PM -0400, David Hurst wrote:

>Have an old Gateway 2000 P5-60 "antique' that still runs fine.  I am
>passing it along to my mother in law who wants to become internet
>certified *g*.  The machine has been matched with an external 28.8
>modem.  Want to install a 56k internal modem in this machine.. Can a
>P5-60 mhz machine accept a 56k modem ?

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