WinPatrol by BillP Studios is a great tool to add to your computer security. WinPatrol has many features in addition to monitoring and detecting changes to your system. Both the free and Plus versions run in real time, no added junk in either download. It uses little resources and will also run on 64 bit systems along with your AV. The latest upgrade this month includes support for the Palemoon browser. I have been using WinPatrol with WSA close to a year with Windows 8.1 on a 64 bit system with 8g of ram. I have not had any issues and I have found it very useful.

 

You can find the information on the upgrade here  http://www.winpatrol.com/upgrade.html