I just got a new (to me) 27" monitor as an upgrade to my old 22" Acer (with the hope to eventually do dual monitors). The only way I can get it to work is to boot the PC (Motherboard: ASRock B450 Pro 4) while connected to the old monitor, and then taking the (HDMI to DVI) cord out of the old monitor and plugging it into the new one. Then the new monitor works, but it is stuck at the resolution of the smaller monitor. If I ever restart the computer, the new monitor will never get a signal from the computer and will just show a "No Signal" message.
I've tried using other cables (pure HDMI, old school D-SUB) with both monitors, together and separately. The only time my computer recognizes a monitor at all is when ONLY the old monitor is connected and ONLY the way it was when I first built my computer: with the HDMI-to-DVI adapter cable.
The motherboard has three video ports: VGA (DB-15), DisplayPort, and HDMI (4k capable).
Here's all the info I've managed to gather:
Graphics: I'm using the integrated Radeon RX Vega 11 Graphics from my Quad-CoreAMD Ryzen 5.
scott@scott-desktop:~$ xrandr xrandr: Failed to get size of gamma for output default Screen 0: minimum 1920 x 1080, current 1920 x 1080, maximum 1920 x 1080 default connected 1920x1080+0+0 0mm x 0mm 1920x1080 77.00*
scott@scott-desktop:~$ inxi -Fxz System: Host: scott-desktop Kernel: 4.9.0-8-amd64 x86_64 (64 bit gcc: 6.3.0) Desktop: Xfce 4.12.3 (Gtk 2.24.30) Distro: Debian GNU/Linux 9 (stretch) Machine: Device: desktop Mobo: ASRock model: B450 Pro4 UEFI: American Megatrends v: P1.30 date: 07/04/2018 CPU: Quad core AMD Ryzen 5 2400G with Radeon Vega Graphics (-HT-MCP-) cache: 2048 KB flags: (lm nx sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3 svm) bmips: 28744 clock speeds: max: 3600 MHz 1: 2300 MHz 2: 1600 MHz 3: 1600 MHz 4: 1600 MHz 5: 2300 MHz 6: 1600 MHz 7: 1600 MHz 8: 1600 MHz Graphics: Card: Advanced Micro Devices [AMD/ATI] Device 15dd bus-ID: 38:00.0 Display Server: X.Org 1.19.2 drivers: fbdev,ati (unloaded: modesetting,vesa,radeon) Resolution: email@example.com GLX Renderer: Gallium 0.4 on llvmpipe (LLVM 3.9, 128 bits) GLX Version: 3.0 Mesa 13.0.6 Direct Rendering: Yes Audio: Card-1 Advanced Micro Devices [AMD] Device 15e3 driver: snd_hda_intel bus-ID: 38:00.6 Card-2 Advanced Micro Devices [AMD/ATI] Device 15de driver: snd_hda_intel bus-ID: 38:00.1 Sound: Advanced Linux Sound Architecture v: k4.9.0-8-amd64 Network: Card: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller driver: r8169 v: 2.3LK-NAPI port: d000 bus-ID: 25:00.0 IF: enp37s0 state: up speed: 100 Mbps duplex: full mac: <filter> Drives: HDD Total Size: 480.1GB (5.7% used) ID-1: /dev/sda model: ADATA_SU650 size: 480.1GB temp: 42C Partition: ID-1: / size: 432G used: 19G (5%) fs: ext4 dev: /dev/sda2 ID-2: swap-1 size: 7.44GB used: 0.00GB (0%) fs: swap dev: /dev/sda3 Sensors: None detected - is lm-sensors installed and configured? Info: Processes: 239 Uptime: 18 min Memory: 1356.3/6970.5MB Init: systemd runlevel: 5 Gcc sys: 6.3.0 Client: Shell (bash 4.4.121) inxi: 2.3.5
Happy to gather any other info or try anything that might be helpful, but I've never had a monitor not "just work" so I'm at a loss as to how to proceed from here.
Thanks for your help!