Q155603: Some S3 Video Cards Do Not Set Refresh Rate Properly

Article: Q155603
Product(s): Microsoft Windows NT
Version(s): winnt:4.0
Operating System(s): 
Keyword(s): kbdisplay
Last Modified: 10-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Server version 4.0 
- Microsoft Windows NT Workstation version 4.0 
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SUMMARY
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Due to differences in BIOS mode tables, some S3 video cards do not set the
proper refresh rate from the Display tool in Control Panel.

MORE INFORMATION
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Windows NT determines the display mode options by obtaining display mode
information from the video card BIOS mode tables. On occasion, because of
differences in manufacturers and BIOS revisions, this results in a different
refresh rate being used after reboot than the setting you selected.

On the Diamond Stealth 64 Video 2001 video card, for example, the following modes
are not set correctly:

- 800 x 600 x 65536 Colors at 120hz (actually displayed at 100 Hz)

- 800 x 600 x True Color at 90hz (actually displayed at 75 Hz)

- 800 x 600 x True Color at 100hz (actually displayed at 75 Hz)

- 800 x 600 x True Color at 120hz (actually displayed at 75 Hz)

The Diamond video card cannot display the higher modes at the refresh rate
displayed by the BIOS, so the BIOS automatically uses the highest possible
refresh rate (in these cases, 100 or 75 Hz).

Additional query words: prodnt

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Keywords          : kbdisplay 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : winnt:4.0

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