I assume slower operation is to be expected when the operating system is encrypted. I had ubuntu 14.04 installed, doing the 1st encryption it asked about, i.e. operating system. Then I also had it encrypt my folders. The system has an AMD Athlon X2 5200+. With all of that, would it be normal for it to be so slow that the mouse is only very intermittently (once every 15 or 20 secs) responsive? Any thoughts?

I use encrypted block device with filesystem on top using cryptsetup. But my system runs fine.

May be the encrypted folders would be the reason for slowing your system.

No, the problem has nothing to do with your encryption. Your problem is either your CPU (throttling) or your video card. Unity is hard, hard on video memory.

I've noticed that if I run out of RAM and need to start swapping, my system does something similar. Are you low on free RAM?

Each time I have installed an operating system, I have wiped the hard drive completely. I have tried Ubuntu 14.04 and Linux Mint 17.1. The results have been the same for both installations. The mouse is only periodically active but 90% of the time it is dead. It works well up to the point that I logon to the machine. The machine is a HP Pavilion, a6337c, with Nvidia Geforce 6150 SE graphics. It has a 500G hard drive and 3072M of RAM. I did the Ubuntu install, wiping the drive each time, with and without the encryption. It made little difference. I tried the advice given for the Mint installation and set the graphics process way down. The results were the same.

I have now wiped the drive and installed Ubuntu 12.04 and let the update manager bring it up to date. It works just fine. It does appear to be something to do with the 14.04 LTS version that causes the problem.

I will next update my graphics driver and then upgrade from 12.04 to 14.04.1.

If the results are the same, I guess I will have to reinstall the 12.04 and be happy that I have something that works.

If that's the case, then have you considered trying one of the other "flavors," such as Xbuntu, Kubuntu, and Lubuntu? They are all essentially the same, just a different desktop environment and different applications installed by default.

So, I have finally done the upgrade from 12.04 to 14.04. The mouse problem seem to be gone. So, updating the Nvidia driver was probably the problem. However, that the 14.04 system was so unresponsive without the driver makes doing it directly impossible. Recall that I had completely wiped the drive before doing the installation. 12.04 ran with its installation driver and made the drive update possible.

Thanks to all who responded. You gave me the where with all to get it done. 73s

As I said...

"Unity is hard, hard on video memory."