Lost second display

I have an msi GS63VR 7RG with an NVIDIA Corp GP104M (GeForce GTX 1070 Mobile) running Ubuntu 1804.

Everything was happy, UNTIL, we decided to upgrade Tensorflow which meant upgrading Cuda etc… After getting Tensorflow compiled and ready, running it failed, explaining that the Kernel was out of date. Indeed, Ubuntu 1804 ships with kernel 4.15, and currently, kernel 4.19 is the most recent. According error message, I needed 4.16 at least, so, playing it save, I loaded 4.16 and rebooted. Everything’s great except that now I don’t have a second display. Error message this time, suggests that the driver is the culprit. So, I upgraded to 410. That didn’t help. So, I went back to 396. That didn’t work either, so it’s back to 390, which I know won’t work with the latest Tensorflow that I just compiled, but at least I’ll have the second display back. Wrong!!

To make a long story short, I’ve been messing around with it, on and off, for almost 2 days and with it back to the original combination (driver 390, Kernel 4.15 and Cuda 9.1) I’m still limping along with the single laptop display and because I’ve gone back, I can’t run Tensorflow either.

I’m wondering if anyone else has experienced this, oh, and if whoever that may be, has suffered through it long enough to have found the fix??

Very few people will see this post in this area. Try here instead:
https://devtalk.nvidia.com/default/board/58/cuda-setup-and-installation/