Also, be aware that no amount of single app (OBS Studio) settings advice can take into account what else you have running on that computer. Over time (decades), default Windows OS is running more and more in the background. And some poorly written apps (including Microsoft) think preloading their bloatware to enable quicker startup is desirable degenerates. Anyway... point being... it is up to you to look into what services (OS native and whatever has been installed) and adjust accordingly. And turning off OS eye-candy, maybe, depending on performance impact.
Learning real-time hardware resource monitoring is always useful. Make sure you don't have something like a Disk I/O, RAM, etc bottleneck
Lots of threads on OS optimization for under-powered hardware. but it is more art than science due to different users needs and priorities