Why does my cpu resources are spiking when im running background apps

Why does my cpu resources are spiking when im running background apps

i have intel i5 4460, 8gb ram, gtx660 and 600watt psu. i tried playing valorant with discord or obs studio running in background but it started to lag. Any ideas as to what is the problem? I was puzzled as to why it happens when my cousin runs the same with his intel i5 3rd gen, 8gb ram and a gt730 but it runs smoothly.