Macintosh 630 Family: Display Resolution and Color Depth

What is Resolution?

Resolution is the number of pixels (dots) a monitor can display on the entire screen. The more pixels there are, the higher the resolution. For example, a resolution of 640x480 is a total of 307,200 pixels on the screen (640 pixels horizontally and 480 pixels vertically). A resolution of 800x600 is 480,000 pixels. The increased number of pixels on the screen provides for a more detailed, crisper image ð as well as slower screen-related processing (such as displaying an image).

What is Color Depth?

Color depth is the number of colors or shades of grey that a single pixel can display, which depends on the number of bits in memory each pixel uses (each byte of memory equals eight bits). The more bits-per-pixel used, the more colors and shades of grey you can display and the more video RAM you need to store the information. (The 630 family includes 1MB for video RAM.) For example, a color depth of one bit can display black or white. An 8-bit color depth can display 256 colors or shades of grey (the bits in one byte can be combined 256 different ways). A 16-bit color depth can display 32,768 colors. You can tell the video RAM needed by multiplying the resolution by the color depth (example: 640 times 480 times 2 (bytes) equals 614,400 bytes or 614K)

Resolution and Color Depth Table

Resolution	Scan Rate	Color Depth	Video RAM	Most Common Displays and Options
640 by 480	60Hz	32,768	614K	Multiple Scan 15 Display
				Apple Presentation System
				Apple TV/Video System
640 by 480	67Hz	32,768	614K	Performa Plus Display
				Apple Color Plus
				Apple Presentation System
				Apple Video System
800 by 600	60Hz	256	480K	Multiple Scan 15 Display
				Apple TV/Video System
800 by 600	72Hz	256	480K	Multiple Scan 15 Display
				No support for Apple TV/Video System
832 by 624 (1)	75Hz	256	519K	No support for Multiple Scan 15 Display
				No support for Apple TV/Video System

Notes:
(1) The resolution switching software, which is built into the Macintosh 630, lets a Multiple Scan Display use the 832x624 resolution. However, the video-in and TV tuner features of the Macintosh 630 will not work properly at this resolution.

(2) Full screen video capture and output is only supported at the 640x480 resolutions. This requires the Apple TV/Video System or Apple Video System to capture video and the Apple Presentation System to output video.

The following computers are in the Macintosh 630 family: Performa 630, Performa 635, Performa 636, Performa 637, Performa 638, LC 630, and Quadra 630.