I have a Win7 Pro 64-bit SP1 desktop with an AMD Radeon HD 6790 HIS GPU. Yesterday it was connected via its two DVI connectors to two monitors: a Samsung 930B and an Asus WC247H-P. The Samsung is dying, so I bought a new 4k LG (27UP80B-W) monitor to replace it, anticipating that I'll be replacing the whole Win7 computer before the end of the year.
I have the LG monitor connected to the Win7 through an HDMI 2.1 cable, and the Asus through its same DVI connection as before. I know the GPU doesn't support 4k, but the LG monitor should still be able to run at a lower resolution.
On startup, the LG monitor receives the signals via the HDMI to show the data from the motherboard (Sabertooth x58) and the Bios, and it gets the black "Windows is Starting" screen. But as the blue Windows "welcome" screen appears, the display switches to the Asus only. The LG says "No Signal. Entering power saving mode." and goes off.
The LG shows up in the System Devices as a Generic PnP Monitor. In the Display settings, it shows up as "LG Ultrafine" but the resolution/orientation/advanced settings/make this the primary display are all grayed out.
There are no Win7 drivers for this monitor in the LG website. I've tried LG phone and online chat support, and they have not been able to resolve this issue.
When I connect the LG monitor to a Chromebook via HDMI, it connects instantly without issue.
Why can Win7 see this monitor but not successfully connect with it so I can use it? Are there GPU settings that need adjusting?
Any advice would be greatly appreciated.
