jmanflooppy

It's more efficient to use molten salt then to heat water, because it is more stable. And a CPU wouldn't be able to get salt hot enough. 
The concept wouldn't work unless using a really high powered CPU, it could work for a large super computer, but just wouldn't make sense for a desktop. And conservation of energy wold render it useless anyway. 
Nice idea but it would have been done before. 

not possible in any sustainable way, while the concept itself would produce some energy its only a tiny little bit, these processes scale very well when going up in size but small scale generators like this are not really efficient.

not possible. conservation of energy, there will always be losses, so your getting much less power than the computer is using.