I configured three monitors (generic non-pnp monitor) using Nvidia?s control panel application for clone support at 1920 x 1080, three monitors are using by HDMI. I’ve the following hardware Nvidia GEforce GT745M, driver version 21.21.13.7270.
If we change the date from BIOS and do a cold reboot, Nvidia driver and services together change the monitors in extended mode. This is not acceptable by our customer.
What can be done to prevent this?
It seems after some research that people face similar problem that points to the Nvidia driver?s auto detection mechanism and it overrides the last saved configuration. I?ve seen some users are putting tape on pin19 to disable auto detection after configuration.
Is there any specific IRP for auto-detection that a filter driver can block?
Can any Nvidia member help in this regard?
Thanks,
Hakim
xxxxx@yahoo.ca wrote:
I configured three monitors (generic non-pnp monitor) using Nvidia?s control panel application for clone support at 1920 x 1080, three monitors are using by HDMI. I’ve the following hardware Nvidia GEforce GT745M, driver version 21.21.13.7270.
If we change the date from BIOS and do a cold reboot, Nvidia driver and services together change the monitors in extended mode. This is not acceptable by our customer.
What can be done to prevent this?
It seems after some research that people face similar problem that points to the Nvidia driver?s auto detection mechanism and it overrides the last saved configuration. I?ve seen some users are putting tape on pin19 to disable auto detection after configuration.
Is there any specific IRP for auto-detection that a filter driver can block?
I just completed a manufacturing test system for a device that has six
video outputs from a pair of Nvidia cards – essentially a video wall.
We encountered much the same problem that you describe. The behavior
seemed almost chaotic; just when I thought I had a recipe that came up
the same way every time, we’d get some kind of a change in ordering or
BIOS or system or moon phase that caused the configuration to slip into
something else.
In the end, I was forced to write a tool to run at boot time to use
EnumDisplayDevices, EnumDisplaySettingsEx and ChangeDisplaySettingsEx
to put the monitors into our exact desired configuration. There is a
newer API for doing display management, but I forget its name.
Even the simple question of “which \DISPLAY device maps to the bottom
port on the left-hand Nvidia card” cannot be answered reliably using
Windows APIs. It CAN be done with the Nvidia SDK, but I didn’t want to
go there. I ended up hacking the registry to find the EDID for each
monitor in order to do that mapping. It was shockingly difficult, and
extremely delicate.
–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.
Thanks Tim for sharing similar experience and suggestions.
I’ve tried using Windows API to clone but I find it does not do cloning but stores the settings in the registry for my hardware. So, if I clone using Nividia’s application and then run the application it seems to store the settings in registry. However, if I change the date and cold reboot then I get two monitors cloned and the third monitor is blank.
I thought I decided to give you an update. I tried windows API and it did not work reliably. Then I tried NvAPI SDK and it worked on restart but if I did a cold reboot then one of the monitor would become extended for whatever reason. So, my start up application would first extend all monitors then clone them all and it worked both for hot and cold reboots.