RAM usage problem in Fedora 3

[Vendra, Hari Prasad V V P Ch S (Hari Prasad)]

Hi,
	I am using Fedora 3  Kernel 2.6.9-1.667 
            without running any user applications
	the RAM usage is increasing in a short time.
	My machine has 512MB RAM.
	I am using "top" command for checking
            RAM usage. Any suggestions please

Hari