ps1.exe is registered as a pacimedia.com downloader. This process usually comes bundled with a virus or spyware and its main role is to do nothing other than download other viruses/spyware to your computer.
This process is a security risk and should be removed from your system.
Please see additional details regarding this process.
Non-system processes like ps1.exe originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that over time your registry suffers fragmentation and accumulates invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues