Sorry if my question is dumb. But its my first coin with POS and i dont really get it.

About 7h ago my wallet showed a few k as Balance and 98% of my Coins under Stake.

About 5 min ago there where 80% Balance and 20% under Stake.

And now there is no Stake Coins and all under Balance.

I got mined coins. But i dont get the Balance/Stake. Should not everythin be at Stake that is older than 2h??

Also should the PC need that much CPU Power while staking? Or should i reboot him if something else uses the CPU???