What you are conceptualizing is something like this kind of a heater:

When you folks in the cold country heat your house, you run some kind of fuel through a furnace, to burn it and produce heat. Think about a fuel oil fired furnace. Now, think about this. The fuel oil doesn't care at all how it is burned. As long as it is burned fairly cleanly, it will produce the desired heat.

Get yourself a little, 3 cylinder, Kabota diesel engine. Run the engine off the fuel oil. The fuel oil doesn't care. When the exhaust comes out of the engine exhaust pipe, run it through a heat exchanger, and heat your house.

At the same time, run a generator with the engine, and use the electricity to produce electric heat. Literally cut your heating bill in half.

If you are going to run a computer so hot that you have enough heat to heat your house, why waste the heat? Do what these guys are suggesting, mine bitcoins through a mining pool, and heat your house at the same time.