So, after much struggling and a few reinstallations, I got my nVidia Geforce 8400 GS mining by installing the correct drivers, nvidia-cuda-toolkit, openssl, automake/autoconf, and cudaminer. The trouble is, while mining I can do hardly anything else efficiently. The next thing I'm going to try is doing it it another terminal screen using ctrl+alt+F2.
So I had the idea that I could use the onboard video for actual video and then just mine with the card. It really wouldn't change my life too much to do so. So I enabled the IGN on BIOS and then restarted, and tried to run Cudaminer again. No good result there. So I reenabled the nVidia card and what happened? Still no Cudaminer working. And now I'm reinstalling Xubuntu 14.04 again to recreate the situation where I had it mining (47KHs was nice compared to the 1.87 I was getting with just the CPU before -- I know, I know, I'm buying some mining equipment soon.)
So what I want to know is if there is a way to do what I had in mind, that is utilize the onboard video for video output but still mine with the the Geforce?
Let me know if any part of this didn't make sense.