Physical RAM usage too high when idle?

[glasscandle]

I am running Windows 7 64-bit on a barely 6 month old ASUS laptop. I have 4GB RAM and an i7-720QM CPU. When my system is idling, my CPU usage is very low, but my physical RAM usage hovers around 47%. Is this normal or too high? The percentage has me worried. What would be causing this?

[Devasis]

When your system is in the idle condition then also lots of the background process are running to keep the system live which is dependent on the process that are running. I will advise you to check in Task manager's process tab and see for the unknown process that is easting maximum CPU usage. And kill if not necessary.