@ossobuco,
I can post calmly now, sheesh, for a while.
From what I have read online, and I'm just starting, it relates to the cpu.
I've had this flibberty cursor before - much whining by me in 2009.
That time it turned out to be a hard drive fix. I figure I am facing that again.
This is not a simple cursor jump, here to there when you didn't mean it.
It is the cursor doing a major shimmy and then going into bells.
Among the traits is that if one is posting on a response window, the cursor will go to hell, as in many blank pages, and you can't control it.
This first happened to me a lot of years ago and people thought I was merely confused.