I am trying to get my home PC more quiet, and have switched my old CPU fan to a Zalman CNPS7700-CU. I soon will change the GPU and chassis fan to Zalmans too. I want to monitor the CPU temperature, and found SpeedFan, which can show a graph of the temperatures, read RPMs and voltages. It can also read S.M.A.R.T information from hard drives, if you want to know the health of your drives. HDD Health is another tool that can be helpful when monitoring drives, and can be set to trigger alarms on events.