I sometimes wonder if I'm getting too old to fiddle around with Linux as my main desktop at home. I'm no longer reading mailing lists or forums and my friends have all moved to Mac OS X.
Today was one of those days. I fired up Kivy and PyCharm this morning, hoping to punch out a quick touch-paint example for my son's lesson. Unfortunately, Kivy had stopped working, spitting forth odd complaints about [WinPygame] Video: failed.
After I figured out that the error was related to the nvidia 3D driver, I decided to rollback the video driver version from nvidia-325 to nvidia-current 304. When I rebooted my system, I could no longer get into X, leaving me with a text console and odd errors complaining that the kernel module was still trying to load the nvidia-325 module.
At this point, I'm thinking that the coffee isn't kicking in, I'm getting too old, and that I don't really want to be messing around with kernel modules. sigh. I just wanted to write a python script.
After an hour of messing around with kernel modules and X configurations, I decided to simply add the xorg-edgers 3rd party repository into my apt repository list and use apt-get to install nvidia-325.
I reboot and kivy starts working again.
I am not sure what started the problem. When kivy stopped working, Pygame was still working. I suspect that the nvidia driver or some graphics library got automatically updated, causing some graphics problems with kivy.
I notice that the newest version of the nvidia driver is 331. I don't think I'll upgrade it right now.
To revert to official packages, install the ppa-purge package and run "sudo pp-purge xorg-edgers"
Driver for Ubuntu 14.04 Trusty Tahr is nvidia-340.
Update September 12, 2014
I used this great blog post on installing the latest Nvidia drivers on Ubuntu 14.04 Trusty Tahr.