random freezes of entire laptop

a few weeks ago i reformatted my laptop, did the usual reinstall software, update windows, driver updates. Since then I have a strange problem where my entire laptop freezes for 5-30 seconds. I have no clue what this could be, there is no error that seems to come up and seemingly no other symptoms... it just freezes then recovers. Any idea what this could be or where I could start to find out?

Thank you in advance,
Aaron