Apple Power Macintosh 7300 series - PC Compatibility Card - Manual (Page 158)

Fixed-frequency monitors
The following tables list the resolutions supported on fixed-frequency
(non-multiscan) monitors. The color depths for 1 MB and 2 MB of DRAM
are also listed. You cannot change refresh rate and other timing items for
fixed-frequency monitors.
Macintosh 21-Inch Color Display
Refresh rate: 68.7 kHz (horizontal), 75.08 Hz (vertical)
Color depth (bpp)
Resolution 1 MB 2 MB
640 x 400 16 16
640 x 480 16 16
800 x 600 8 8
1024 x 768 not supported 8
Macintosh 21-Inch Monochrome Display
Refresh rate: 68.7 kHz (horizontal), 75.08 Hz (vertical)
Color depth (bpp)
Resolution 1 MB 2 MB
640 x 400 16 16
640 x 480 16 16
800 x 600 8 8
1024 x 768 not supported 8
158 Appendix E