I posted the same problem last night. I'd cured mine.. Here's a copy of my post, hope it helps.......
I've recently experience my GPU load is high (98%) on idle, with the fan racing away at very high speed. After ferreting around I finally found the problem.
In the Windows folder, look for a folder called Temporary. In this folder, among other files there is a file called iehighutil.exe.
If it's there, that's your problem. I'm on new territory here but I'll try.. It's a program that uses your GPU to it's maximum in order to get bitcoins, whatever they are. Nasty little virus that's going to fry your GPU if not stopped.
Easy to get rid of, kill the process in task manager, then delete the Temporary folder - everything in that folder is to do with the very same virus.
Hope this helps. This is my first post here as a newbie! So I'll say hello at the same time.
Since deleting that folder my computer has been purring along like a kitten, no problems at all.