Kali constantly hangs

I have installed Kali 2017.2 32bit on about 8 year old 32bit Dell PC.

As I'm working on it, editing files, running commands, etc., it will constantly
hang about every minute or so. Nothing works - clicking mouse, moving windows
typing in a command window. After a few seconds, it reverts to normal, then repeats.
This is consistent.

I then reinstalled, but this time 2017.1; same problem. Will try a 2016 version.

But in the meantime, any ideas? I did read one comment about maybe an incorrect video setting but didn't
go beyond that.

type dmesg in the terminal just after you have problems, anything in red ?

I'd also run top, and see if anything is consuming excessive resources

Rig overclocked and/or overheating?