EDIT: I finally realized that there are two different versions of Linux listed in the Grub booting menu
If I pick
3.13.0-32 the keyboard and mouse will work. But if I pick
3.13.0-39 I have no mouse or keyboard.
Last week I installed Ubuntu 14.04 on a Dell Optiplex 760. The whole install worked fine and I started getting everything on the machine set up to my liking (installing chrome, email client, mapping a shared drive). I rebooted several times during this process and had no issues.
I come back to it this morning and now I cannot get any keyboard or mouse to do anything inside of Ubuntu. I have tried different keyboards/mice and different USB ports all with no effect.
While the machine is booting up it does recognize keyboard and mouse because I can use them to press F2 which will take me to the BIOS and then I can navigate around the BIOS with both mouse and keyboard. So I know all of the hardware is working fine.
Searching around online I've found a lot of stuff talking about VT-d and enabling IOMMU but I don't see any option for anything by either of those names in the BIOS and I don't know enough about either of them to even know where else to start looking.
Since I can't get keyboard or mouse working I can't run any commands to help with diagnostics.
However I am able to boot from the install CD and alter files on the hard drive. I tried adding
intel_iommu=soft to the file
/etc/grub.d/40_custom based on a suggestion I found while searching for this issue and device model #. That does not seem to have had any effect though to be honest I am not certain I actually put it in the right spot.
Does any one have suggestions for further diagnosing or solving this issue so that I can correctly use mouse / keyboard on my machine?