Ubuntu – Dual monitors only work in Ubuntu 16.04.1 Gnome when set to different resolutions (AMD R9 380)

I have a DVI + HDMI dual monitor setup with an AMD Radeon R9 380. I can't use both monitors at max resolution though. One monitor can be at max resolution and the other must be something different. If I set them to the same resolution, one of the screens is blank but still seems to be receiving a signal because it doesn't turn off.

Here is the output from lshw -c video

crawforc3@ubuntu:~$ sudo lshw -c video
  *-display               
       description: VGA compatible controller
       product: Tonga PRO [Radeon R9 285/380]
       vendor: Advanced Micro Devices, Inc. [AMD/ATI]
       physical id: 0
       bus info: pci@0000:01:00.0
       version: f1
       width: 64 bits
       clock: 33MHz
       capabilities: pm pciexpress msi vga_controller bus_master cap_list rom
       configuration: driver=amdgpu latency=0
       resources: irq:128 memory:e0000000-efffffff memory:f0000000-f01fffff ioport:e000(size=256) memory:f7e00000-f7e3ffff memory:f7e40000-f7e5ffff

output from xrandr

crawforc3@ubuntu:~$ xrandr
Screen 0: minimum 320 x 200, current 3600 x 1080, maximum 16384 x 16384
DisplayPort-0 disconnected (normal left inverted right x axis y axis)
HDMI-A-0 connected 1680x1050+1920+30 (normal left inverted right x axis y axis) 527mm x 296mm
   1920x1080     60.00 +  50.00    59.94    30.00    29.97  
   1920x1080i    60.00    50.00    59.94  
   1680x1050     59.88* 
   1280x1024     75.02    60.02  
   1440x900      59.90  
   1280x960      60.00  
   1280x800      59.91  
   1152x864      75.00  
   1280x720      60.00    50.00    59.94  
   1440x576      50.00  
   1024x768      75.08    70.07    60.00  
   1440x480      60.00    59.94  
   832x624       74.55  
   800x600       72.19    75.00    60.32    56.25  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    66.67    60.00    59.94  
   720x400       70.08  
DVI-D-0 disconnected (normal left inverted right x axis y axis)
DVI-I-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 527mm x 296mm
   1920x1080     60.00 +  50.00    59.94*   30.00    29.97  
   1920x1080i    60.00    50.00    59.94  
   1680x1050     59.88  
   1280x1024     75.02    60.02  
   1440x900      59.90  
   1280x960      60.00  
   1280x800      59.91  
   1152x864      75.00  
   1280x720      60.00    50.00    59.94  
   1440x576      50.00  
   1024x768      75.08    70.07    60.00  
   1440x480      60.00    59.94  
   832x624       74.55  
   800x600       72.19    75.00    60.32    56.25  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    66.67    60.00    59.94  
   720x400       70.08  

And contents of ~/.config/monitors.xml

<monitors version="1">
  <configuration>
    <clone>no</clone>
    <output name="DVI-I-1">
      <vendor>ACI</vendor>
      <product>ASUS VN248</product>
      <serial>ECLMTF168617</serial>
      <width>1920</width>
      <height>1080</height>
      <rate>59.940200805664062</rate>
      <x>0</x>
      <y>0</y>
      <rotation>normal</rotation>
      <reflect_x>no</reflect_x>
      <reflect_y>no</reflect_y>
      <primary>yes</primary>
      <presentation>no</presentation>
      <underscanning>no</underscanning>
    </output>
    <output name="HDMI-A-0">
      <vendor>ACI</vendor>
      <product>ASUS VN248</product>
      <serial>ECLMTF168622</serial>
      <width>1680</width>
      <height>1050</height>
      <rate>59.883251190185547</rate>
      <x>1920</x>
      <y>30</y>
      <rotation>normal</rotation>
      <reflect_x>no</reflect_x>
      <reflect_y>no</reflect_y>
      <primary>no</primary>
      <presentation>no</presentation>
      <underscanning>no</underscanning>
    </output>
  </configuration>
</monitors>