Windows 10 core usage when "idle"

AuroraSCII

Commendable
Oct 18, 2016
13
0
1,520
Greetings!

So I left my pc running while I was at work today, downloading large files from steam, uplay and via Jdownloader.

When I took a look at MSI Afterburners' hardware monitoring, I noticed that while I was away, apparently only one core was being used at a solid 100%, whereas the other 3 cores were very close to being idle (0 to 20% usage).

As soon as I started using the PC, this changed and the cores were evenly used again.

https://gyazo.com/f3ad20c8117e85adfd88daa65c56dc91

Should I worry about this issue?
And what might cause it?

Fondest regards