PC Housekeeping and System Maintenance

Until fairly recently, I have maintained a somewhat casual approach to the system maintenance of my PC. “Casual” in this context is a subjective term. What I consider to be “casual” others may think to be robust or even rigorous. But I digress. I regularly undertake minor housekeeping such a clearing my web browser data, removing temporary or unwanted files and updating software. I also make sure that only essential services and programs start when I turn on my PC. I keep an orderly desktop and an intuitive filing system. However, I do very little with respect to maintaining the hardware inside my PC. I clean inside the case a couple of times a year and ensure that the fans are free from dust contamination but that’s about it. I have no idea if the installed RAM is running optimally or whether the processor is operating within the appropriate heat threshold. Does the thermal paste between it and the heat sink need replacing? Are all the cores enabled?