What utilities should you run once a month to maintain the speed of your PC?

To maintain the speed of your PC, you should run disk cleanup utilities to remove temporary files and unnecessary system files, and use a disk defragmentation tool if you're using a traditional HDD (not needed for SSDs). Additionally, consider running an antivirus scan to check for malware and using system optimization tools to manage startup programs. Regularly updating your software and drivers can also help maintain optimal performance.