Graphics Card: NVidia 460 GTX.
Driver: NVIDIA accelerated graphics driver (version current)
I have one DVI monitor, an old Dell LCD from 2005, and one VGA monitor, an Asus ML238H from 2010 whose HDMI port broke. The Asus is plugged into my graphics card's primary monitor slot and is the better monitor even though it is VGA but my computer defaults to the Dell. This happens when I boot as well; the loading screens, the motherboard brand image, etc. are all displayed on the Dell monitor until Windows loads. Then both monitors work.
The same thing happened when I booted up Ubuntu 12.04 but I did not see the second monitor when the log-in screen popped up, nor did I when I logged in. I went to System Settings/Displays and my Asus monitor is not an option. I clicked Detect Displays and the Asus is not detected.
I looked at the other questions regarding NVIDIA drivers and recalled my problems with Ubuntu a few years ago and decided to check the driver. I went to Additional Drivers to install the proprietary driver and it looks like it's installed and active but I'm still having this problem. There is another driver option, the post-release NVIDIA driver, but that does not fix the problem either.
Also, under System Details/Graphics the graphics device is listed as Unknown, which might indicate that it is using an open source generic driver and not the proprietary NVidia driver. But under Additional Drivers it says that I am using the NVidia driver.
Any help is appreciated.