Viewsonic VX2835wm on an nVidia card under Windows 7 with a DVI to HDMI cable
After upgrading my desktop to Windows 7, my second head (a Viewsonic VX2835wm) was showing a horribly overscanned image (blurred text, edges cropped). After fiddling with the monitor settings and setting the aspect ratio to 1:1, I then ended up with letterboxed image, with missing information around the edges (eg, the Windows start menu was off screen).
According to nVidia, this should already be accounted for in their drivers (from the release notes for 191.07):
Some HDMI TVʹs have a native resolution that exceeds the maximum supported HD
mode. For example, TVs with a native resolution of 1920x1200 exceed the maximum
supported HD mode of 1920x1080.
Applying this native mode results in display overscan which cannot be resized using
the NVIDIA Control Panel since the mode is not an HD mode.
To avoid this situation and provide a better user experience, the driver treats certain
TVs– such as the Viewsonic VX2835wm and the Westinghouse LVM‐ 37w3–as a DVI
monitor when applying the native mode. Because the driver does not treat the TV as
an HDMI in this case, the HDMI audio is not used.
Unfortunately, what they say and what the drivers do are completely different.
This post explains how to correct the situation. I'll summarize below:
- Extract the drivers
- Edit NV_DISP.INF and remove these lines from the [nv_clearRegistrySwitches_delreg] section:
- Add the following lines to the [nv_commonDisplayModes_addreg] section (note that Flags0 is for the first monitor, Flags1 is for the second):
HKR,,OverrideEdidFlags0, %REG_BINARY%, 5A,63,1F,0F,00,00,FF,FF,04,00,00,00,7E,01,00
HKR,,OverrideEdidFlags1, %REG_BINARY%, 5A,63,1F,0F,00,00,FF,FF,04,00,00,00,7E,01,00
- Run the installer
For the lazy, I've attached the patched INF to this document.