README for XFree86 on OS/2 : Checking Compatibility of Video Hardware . ... Edit your CONFIG.SYS file to contain the following line somewhere: DEVICE=Y:\XFree86\lib\xf86sup.sys Of course replace ``Y:'' with the correct drive letter. ... Refer to section Adding Variables to CONFIG.SYS below. ... Start a full screen OS/2 CMD session and enter the following command: [C:\] Y:\XFree86\bin\SuperProbe . ... SuperProbe can identify many more video cards than are supported by XFree86. ...