TOPIC
The article discusses the difference between video mirroring and dual video.
DISCUSSION Video mirroring lets you display the same Macintosh image, complete with the menu bar, on two screens simultaneously. The second device can be a monitor, television, or overhead projector depending on the connection you have available. This capability is most useful for those in education or training environments who want to connect large monitors or projection screens to their computer. Video mirroring is built-in on some PowerBooks, and an add-on option to both the Macintosh LC 580 and Power Macintosh 5200 computers. If you do not have built-in or add-on video mirror support, you can still get the benefits of this type of technology if your computer has a standard DB-15 video-out port, by using the Apple Presentation System or similar products from third party vendors. Dual Video Dual video means there are two independent video channels, each with its own dedicated Video RAM (VRAM). On Macintosh computers, this always means there is at least one video card installed. For example, the Power Macintosh 6100 series has built-in video capability, but the addition of a Power Macintosh AV card adds an independent additional video-out capability with a separate amount of VRAM. If you connect one monitor to each port on the Power Macintosh 6100 AV, you would see a "virtual desktop". You could have a window on one screen, your primary display, and a window on the second screen, the secondary display. You can arrange the orientation of the monitors so that the mouse will move between the two monitors at the point where they touch in the Monitors control panel. Only one monitor can display the menu bar, but you can choose which is the main monitor in the Monitors control panel. You do not get two identical images when using dual video. Due to the highly integrated characteristics of this type of multiple device support, you can theoretically have as many displays as you have slots. You could, for example, populate each available expansion slot on your Macintosh computer with a video card, and have that many monitors creating a large virtual desktop. There is no processor performance degradation from the use of multiple displays. The relative performance of each display depends on the performance characteristics of the attached video card. This article was published in the "Information Alley": Volume II, Issue 11, Page 6 |
Document Information | |
Product Area: | Monitors-Displays |
Category: | General Topics |
Sub Category: | General Topics |
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