> I want implement server virtualization but i need to know the hardware 
> requirements to install OpenVZ.
> Hard Disc space, RAM memory, processor speed, etc. so all Operating 
> Systems installed run properly.

I don't think that there are hard requirements. I successfully tested 
OpenVZ with several VPSs on a system with 1 GB of RAM and a 160 GB hard 
drive.

The short version:

a) If your hardware is compatible with the kernel (think Fedora or 
RedHat) then it's compatible with the OpenVZ kernel. The performance is 
not surprising at all: DDR2 RAM is faster than DDR, a Athlon X2 4000+ is 
faster than a Pentium-4, RAID rocks, and so on.

b) Just plan for capacity, and remember that too much is always better
than not enough. An extra GB of RAM, enough disk for the host OS plus 
some to spare, and you'll be A-OK.

-- 
Gregor Mosheh / Greg Allensworth
System Administrator, HostGIS cartographic development & hosting services
http://www.HostGIS.com/

"Remember that no one cares if you can back up,
  only if you can restore." - AMANDA