TITLE
    Duo Docks: Multiple Scan Resolution Switching (1/96)
Article ID:
Created:
Modified: 		17641
4/21/95
1/8/96
TOPIC


    I have a PowerBook Duo 280c with a Duo Dock with 1Mb of VRAM and PowerBook Duo enabler 2.0. I have the Dock connected to a Multiple Scan 17 Display. However, I cannot use any resolutions other than 640x480.

DISCUSSION


    The release of System Software (7.1.1 or 7.5) makes a significant difference when a Duo is inserted into an original Duo Dock. In comparison, the Duo Dock II offers multiple resolutions, when either version of System Software (7.1.1 and PB Duo Enabler 2.0, or 7.5) is installed.

    In an original Duo Dock with System Software 7.1.1, the additional VRAM offers additional colors, but not additional resolutions. In order to access additional resolutions on the Multiple Scan 17 Display, you either need a display adapter (because the Dock does not recognize the sense pins on the monitor cable), or you need the newer version of System Software, version 7.5.

    I tested with one such adapter and while it allows for a higher resolution, it does not allow for switching of resolutions "on the fly". Whatever resolution you select on the adapter, is the only resolution available.

    Display adapters do not increase the number of resolutions a Duo Dock can handle, but they do give you access to all the resolutions that the Duo Dock can support. The highest resolution supported on the original Duo Dock is the 16-in. monitor resolution of 832 x 624.


    Duo Dock with 1MB VRAM
    ======================

    System Display Adapter Resolutions Supported
    ------ --------------- ---------------------
    7.1.1 NO 640x480
    7.1.1 Yes 640x480, 832x624
    7.5 NO 640x480, 832x624


    Duo Dock II and Duo Dock Plus
    =============================

    System Display Adapter Resolutions Supported
    ------ --------------- ---------------------
    7.1.1 NO 640x480, 832x624, 1024x768, 1152x870
    7.5 NO 640x480, 832x624, 1024x768, 1152x870


    Article Change History:
    08 Jan 1996 - Added Duo Dock Plus information.

    Support Information Services

Document Information
Product Area: Computers
Category: PowerBook
Sub Category: Duo Dock & Minidock

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