[CentOS] CentOS 4.3 under VMWare ESX 2.5.3 Server

I have a  IBM XSeries 366 with 04 processors Intel Xeon 3.16 Ghz, 16 Gb 
of memory and a storage IBM with 2 terabytes.
I work with virtualization and my OS in this machine is a VMware ESX 
2.5.3 version. When I install CentOS 4.X as guest operating system under 
ESX,  the performance is very  very bad. When I intsall RHES4 as guest 
operating system under ESX, the performance is very good. It will be 
that it has some problem CentOS to work with virtualization?