Sorry for the delay..
I was disabling the drivers, but I couldn't determine which driver is the one..
And I downloaded "Process Explorer" and I'm not sure what to do with it exactly 4388243883
...

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And this is the CPU with bittorrent on, "System Interrupts" process is here.

This isn't only bittorrent, this happens with anything that is using HDD.

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This is the task manager when the computer is idle.
Everything is smooth, no problems at all.

Thanks for the welcome :)

down here it's when I turn on bittorrent, and it's...

I saw threads about people complaining that their audio and mouse is lagging, but in my case, it happens when I download something with bittorrent or when I'm installing something.
on Win 8.1 and...