glx fails with nvidia proprietary drivers

After installing nvidia-375 normally through the package manager, glx doesn't work.
Running nvidia-xconfig doesn't fix the problem and also brings my resolution down to 800x600 or something.
Installing bumblebee makes glx work, but only on the integrated intel gpu.
This is a laptop with 2 gpus, so I figured it might be some prime stuff going wrong, but nvidia-settings is nearly empty (as seems to be a common issue) for some reason, so there's nothing I can change there. Nouveau works 'fine', I think.

This might also be significant, but if I have nouveau installed and try to switch to the proprietary driver using jockey, it just fails with no error message. When I press 'apply changes', the radio button simply switches back to nouveau by itself.

glxinfo output:
name of display: :0.0
Error: couldn't find RGB GLX visual or fbconfig

glxgears output:
Error: couldn't get an RGB, Double-buffered visual

steam, etc other glx-dependent applications also fail to run

/var/log/Xorg.0.log:
https://pastebin.com/AeqYLvcU
the only GLX-related error message I can find is this:
[ 17.228] (EE) Failed to initialize GLX extension (Compatible NVIDIA X driver not found)

sudo lshw -C display:
  *-display
       description: VGA compatible controller
       product: HD Graphics 520
       vendor: Intel Corporation
       physical id: 2
       bus info: pci@0000:00:02.0
       version: 07
       width: 64 bits
       clock: 33MHz
       capabilities: pciexpress msi pm vga_controller bus_master cap_list rom
       configuration: driver=i915 latency=0
       resources: irq:128 memory:dd000000-ddffffff memory:b0000000-bfffffff ioport:f000(size=64) memory:c0000-dffff
  *-display
       description: 3D controller
       product: GM107M [GeForce GTX 950M]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a2
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list rom
       configuration: driver=nvidia latency=0
       resources: irq:16 memory:de000000-deffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:e000(size=128) memory:df000000-df07ffff

ldd /usr/bin/glxinfo:
 linux-vdso.so.1 => (0x00007ffe31dd8000)
 libGL.so.1 => /usr/lib/nvidia-375/libGL.so.1 (0x00007fbac7204000)
 libX11.so.6 => /usr/lib/x86_64-linux-gnu/libX11.so.6 (0x00007fbac6ecb000)
 libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fbac6b04000)
 libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fbac6900000)
 libGLX.so.0 => /usr/lib/nvidia-375/libGLX.so.0 (0x00007fbac66d0000)
 libGLdispatch.so.0 => /usr/lib/nvidia-375/libGLdispatch.so.0 (0x00007fbac6400000)
 libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007fbac61de000)
 /lib64/ld-linux-x86-64.so.2 (0x000055cca7132000)
 libXext.so.6 => /usr/lib/x86_64-linux-gnu/libXext.so.6 (0x00007fbac5fcc000)
 libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007fbac5dc8000)
 libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007fbac5bc2000)