CPU replacements really aren't that hard, it's just very important that you make sure you either match the exact model already in your laptop (a replacement) or find one that is compatible and better than the current one (an upgrade). The second thing is easier said than done - sometimes you'll find your laptop/computer already has the best CPU it can support, because the motherboard can't hold anything else. And so then if you replace the motherboard with a different one, you have a whole new can of worms because now your other components might not work with that motherboard (e.g. memory).