intel i5-6400

Hi, I'm thinking about buying a new PC and if I do that I want to sell my current one. My current system is a 4 year oldprebuilt Acer Aspire TC-780, but I have added a MSI GTX 1050 Ti and an extra stick of 8GB DDR4 2133Hz RAM. It still works perfectly and is still pretty clean from the inside...

In my system i have a i5-6400 and a 750ti 4gb and on some games the cpu will be 100% and the gpu 20-30%.Could this mean that the gpu or the cpu is bottlenecking?

My friend owns a gaming laptop gtx 1050, i5 common pairing. Sometime he dies in game and just start saying "ohhh 0 fps". Is this possible in csgo with a gaming laptop to have 0 fps when he is dieing but can use his mic perfectly fine?