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AST RESEARCH, INC.            TECHNICAL BULLETIN #0886              01-27-94

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                   PREMMIA LX VIDEO RESOLUTION CORRECTIONS


PROBLEM #1:    Table 6-1 in the Premmia LX Product Guide is incorrect.  The
               table lists the video modes supported by the system, but does
               not distinguish between systems that contain the high
               resolution digital-to-analog converter (DAC) and those that
               contain the low resolution DAC.

               Table 6-1 also contains misleading information about which
               video modes are supported.

               Table 1 in this TB provides a corrected list of the supported
               video modes for systems with the high resolution DAC.

               Table 2 lists the supported video modes for systems with the
               low resolution DAC.  We recommend that you replace Table 6-1
               in the Product Guide with the video resolution table that is
               appropriate for your system.

               If you are not sure which DAC is in your system, do the
               following:

               1. Start Windows and open the FlexDesk control panel by
                  double-clicking on the FlexDesk Icon.

               2. Once FlexDesk is open, Type:
                   +  + ATI

               This command tells you which DAC is in the system (as well as
               other information).  The ATI68875 is the high resolution DAC;
               the BT481 is the low resolution DAC.  If your system contains
               the ATI68875, replace Table 6-1 in the Product Guide with
               Table 1 from this TB.  If your system contains the BT481 DAC,
               replace Table 6-1 in the Product Guide with Table 2 from this
               TB.

CAUSE:         Incorrect information in product guide.

SYSTEMS
AFFECTED:      Premmia LX P/N 501288-001 through -004.

SOLUTION #1:   Replace the incorrect information with the tables listed
               below:

                        HIGH RESOLUTION VIDEO DISPLAY

TABLE 1.       Video Modes Supported by the High Resolution Video Display
               (ATI68875 DAC)

RESOLUTION       COLOR     VERTICAL   HORIZONTAL      VRAM
                 DEPTH       HZ          KHZ         REQUIRED
                 BPP

640 x 480         8          60         31.5          1 MB
640 x 480         8++        72         37.0          1 MB
640 x 480         8*         72         44.5          1 MB
640 x 480         16         60         31.5          1 MB
640 x 480         16         72         37.0          1 MB
640 x 480         16         72         44.6          1 MB
640 x 480         24         60         31.5          1 MB
640 x 480         24         72         37.0          1 MB
640 x 480         24         72         44.6          1 MB
800 x 600         8          89 (i)     31.5          1 MB
800 x 600         8          95 (i)     33.8          1 MB
800 x 600         8          56         35.2          1 MB
800 x 600         8          80         37.9          1 MB
800 x 600         8          70         44.5          1 MB
800 x 600         8          72         48.0          1 MB
800 x 600         8          76         52.4          1 MB
800 x 600         16         89 (i)     31.5          1 MB
800 x 600         16         95 (i)     33.8          1 MB
800 x 600         16         56         35.2          1 MB
800 x 600         16         80         37.9          1 MB
800 x 600         16         70         44.5          1 MB
800 x 600         16         72         48.0          1 MB
800 x 600         16         76         52.4          1 MB
800 x 600         24         89 (i)     31.5          2 MB
800 x 600         24         95 (i)     33.8          2 MB
800 x 600         24         55         35.2          2 MB
800 x 600         24         60         37.9          2 MB
800 x 600         24         70         44.5          2 MB
800 x 600         24         72         48.0          2 MB
1024 x 768        8          87 (i)     35.5          1 MB
1024 x 768        8          60         48.4          1 MB
1024 x 768        8          86         53.9          1 MB
1024 x 768        8          70         56.1          1 MB
1024 x 768        8          72         57.9          1 MB
1024 x 768        8          76         61.4          1 MB
1024 x 768        16         87 (i)     35.5          2 MB
1024 x 768        16         60         48.4          2 MB
1024 x 768        16         66         53.9          2 MB
1024 x 768        16         70         56.1          2 MB
1024 x 768        16         72         57.9          2 MB
1280 x 1024       4          87 (i)     35.2          1 MB
1280 x 1024       4          95 (i)     37.9          1 MB
1280 x 1024       4          60         44.5          1 MB
1280 x 1024       4          70         48.0          1 MB
1280 x 1024       4          74         52.4          1 MB
1280 x 1024       8          87 (i)     31.5          1 MB
1280 x 1024       8          95 (i)     33.8          1 MB
1280 x 1024       8          60         35.2          1 MB
1280 x 1024       8          70         37.9          1 MB
1280 x 1024       8          74         44.5          1 MB

     +    bbpmbits per pixel:  4 bpps 16 colors, 8 bpp =  256 colors,
          16 bpp = 65,000 colors, 24 bpp = 16.7 million colors
     ++   32 Mhz setting     *    40 Mhz setting
     (i)  interlaced†

                        LOW RESOLUTION VIDEO DISPLAY

TABLE 2.       Video Modes Supported by the Low Resolution Video Display
               (BT481 DAC)

RESOLUTION       COLOR     VERTICAL   HORIZONTAL      VRAM
                 DEPTH       HZ          KHZ         REQUIRED
                 BPP

640 x 480         8          60         31.5          1 MB
640 x 480         8++        72         37.0          1 MB
640 x 480         8*         72         44.5          1 MB
640 x 480         16         60         31.5          1 MB
640 x 480         16         72         37.0          1 MB
640 x 480         16         72         44.6          1 MB
640 x 480         24         60         31.5          1 MB
800 x 600         8          89 (i)     31.5          1 MB
800 x 600         8          95 (i)     33.8          1 MB
800 x 600         8          56         35.2          1 MB
800 x 600         8          80         37.9          1 MB
800 x 600         8          70         44.5          1 MB
800 x 600         8          72         48.0          1 MB
800 x 600         8          76         52.4          1 MB
800 x 600         16         99 (i)     31.5          1 MB
800 x 600         16         95 (i)     33.8          1 MB
800 x 600         16         58         35.2          1 MB
1024 x 768        8          87 (i)     35.5          1 MB
1024 x 768        8          60         48.4          1 MB
1024 x 768        8          66         53.9          1 MB
1024 x 768        8          70         56.1          1 MB
1024 x 768        8          72         57.9          1 MB
1024 x 768        8          76         61.4          1 MB
1280 x 1024       4          87 (i)     50            1 MB
1280 x 1024       4          95 (i)     50            1 MB
1280 x 1024       8          87 (i)     50            2 MB
1280 x 1024       8          95 (i)     50            2 MB

     +    bbpmbits per pixel:  4 bpps 16 colors, 8 bpp =  256 colors,
          16 bpp = 65,000 colors, 24 bpp = 16.7 million colors
     ++   32 Mhz setting
     *    40 Mhz setting
     (i)  interlaced

PROBLEM #2:    The Premmia LX product guide contains an error which concerns
               the command used to install the video setup program.

SOLUTION #2    On Page 6-5, under "Selecting Resolution and Refresh Rate",
               change the setup command

               From:     A:\setup
               To:       A:\install