Isn't giving GPU computational power this way extremely inefficient? Where can I read more about implementation of this with more technical details?
Are you talking about folding at home?
If so, I don't think it's inefficient at all, if you define efficiency as a measure of wasted resources. All of the power that goes into minining bitcoin simply 'secures the network'. However, we have got to the point where we actually have way more hashing power than we need, so every additional miner is 100% wasting their resources.
Folding @ home on the other hand uses idle gpus (and cpus) to do scientific research for curing diseases. This is not at all a waste of resources if you ask me