graphics very sluggish after unplugging from power

[david-k-lam1]

I'm on 16.04, and this occurs for me with both the opensource driver, and the nvidia 384.90 driver. It happened to me on 14.04 too.

The video card model is a GeForce GTX 850M, and I'm using the driver from the nvidia-384 package following this page: https://help.ubuntu.com/community/BinaryDriverHowto/Nvidia

I'm using this 'glxgears' program to test video performance.

When good, it shows 10,000+ FPS


61373 frames in 5.0 seconds = 12274.539 FPS

When bad, which happens immediately after i unplug my laptop, it shows a sub 100 FPS!


371 frames in 5.0 seconds = 74.048 FPS

Replugging into the A/C power does not fix the issue. It stays at < 100 FPS.

Anyone got any ideas on how to debug it?

[Autodave]

Where did you get the Nvidia driver from? What video card model do you have?

[david-k-lam1]

I got the driver by installing the nvidia-384 package following this page: https://help.ubuntu.com/community/BinaryDriverHowto/Nvidia

It's model is a GeForce GTX 850M