Slow pc lagging in certain scenarios

This is not a problem i faced in manjaro. I moved from Ubuntu. Pc runs fast compared to windows but sometimes it slows down when loading websites on browsers chromium based and firefox and playing 720p videos on youtube in certain videos because i think there is codec differences. Cpu usage hits close to 100%. Is it just that my pc is an old toshiba satellite or is there something i can do?
And its not my internet its just everything becomes laggy and in task manager cpu hits 100% while ram is under 50%.

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Do you have swap file or swap partition? Please help us by providing some information about your system. Please read:

Have you tried to enable hardware video acceleration?

If you haven’t already, also have a check at your task manager & see if there’s anything using a lot of CPU at the time of the go-slow. You might find a clue there. I hope you sort it soon. R :slight_smile: