Nvidia drivers for Loki on an optimus system do not seem to work

Question

I followed the instructions here How to install nvidia graphics driver for nvidia 820m on loki? however if I run

sudo prime-select nvidia
glxgears 

I get

X Error of failed request:  BadValue (integer parameter out of range for    operation)
  Major opcode of failed request:  155 (GLX)
  Minor opcode of failed request:  3 (X_GLXCreateContext)
  Value in failed request:  0x0
  Serial number of failed request:  23
  Current serial number in output stream:  24

I'm using a dell xps 15z and lspci | grep 'VGA\|3D'outputs

00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06)
02:00.0 3D controller: NVIDIA Corporation GK107M [GeForce GT 750M] (rev a1)

I've been trying different things for a while and am stumped.

Answer 1

The problem was actually something obvious. I failed to turn off secure boot correctly. I always thought it was odd that I never seemed to have to enter the password I set, not realizing I was passing over the spot to do it while booting. The windows was so small on my screen to barely be legible. When I did enter the password instead of pressing enter and passing over the prompt the drivers worked.