Microtek C593 User Manual page 11

You can select five OSD languages for your convenience.
You can select display mode as 640 x 400 (graphic mode) or 720 x 400 (text
mode).
Three modes are provided: User Mode, 6500, and 9300. Use the selection
key to select the Color Temperature field, then press - & + to select the
color temperature setting.
Use the selection key to select the Brightness field, then press - & + to
change the brightness value.
In the OSD screen, you will see the Horizontal frequency (HF), Vertical
frequency (VF), display resolution (MODE) and the monitor Firmware
version (ROM LEVEL). These values are automatically detected by the
monitor, and the settings cannot be changed by the user.