Once a day regular occurrence: PC lags or freezes for a mere moment

Question

Somewhat once a day my PC lags or freezes for a second, fans start working louder (like when booting up pc etc) and then everything is back to normal.

All happen very quickly, so there's no huge inconvenience currently, but I'm worried it might be a sign of something bad coming.

So far I can't correlate the occurrences with anything I do. It doesn't seem to correlate with the games I play or other load software-wise.