I have a Ryzen 9 system with AMD Radeon VEGA with three monitors attached, running Win 11.
The three monitors are identical HP V28 4K monitors. Each monitor has two HDMI plus one DP connector.
The mini-PC has three connectors: DP, HDMI, USB-C
Monitor 1: DP to DP -- working fine at 3840 x 2160
Monitor 2: USB-C to DP -- working fine at 3840 x 2160
Monitor 3: HDMI to DP -- only allows 2560 x 1600 resolution
I also tried HDMI to HDMI for monitor 3 with the same result: only 2560 x 1600 resolution. I also tried switching the cables, to make sure that the 3rd monitor is fine -- when it's connected as monitor 2, it auto detects correctly and runs at 3840 x 2160.
The Win 11 Setting menu Advanced Settings has a menu for Hz -- but only 60Hz is supported, there's no 30 Hz option, so it's not an option to set the res at 3840 x 2160 and run at 30 Hz on the 3rd monitor.
In Device manager, the Monitors show three Generic PnP Monitors -- I tried to download device-specific drivers for these monitors, but nothing available.
The AMD Adrenalin software says the 3rd monitor has a maximum resolution of 2560 x 1600 -- I tried to define a custom resolution but I just get an error that 3840 x 2160 is not supported by this monitor. Yet the 3rd monitor is correctly detected as an HP V28 4K.
The manufacturer says to download new drivers and it will work. The mini-PC was advertised that it would support three 4K monitors and everything I see online says that the AMD Radeon VEGA will support this.
How do I get the third monitor to work at 3840 x 2160 resolution like the other two monitors?
Thanks!
