DO the math.
AN Intel XEON Dual Core CPU has e.g 2 x 3000 MHZ.
The Second Core is only 50-75 percent equal to the first core.
VMware says 8 VM's per Core than on the first core each vm has 375 MHZ (3000 MHz ).
The OS's Windows 2003 need's for low end applications 500 MHZ.
So 3000 MHZ / 500 MHZ = 6 VM's per first Core. With this in mind you can garanty each vm 500 MHZ.
One step further the service console of esx needs although resources,
so take 10 -20 % from 3000 MHZ than 2400 MHZ is left for the vm's.
So now you have 5 vm's per first core, if you have to garanty to each vm
500 MHZ.
Next step further if one gigabit card is fully used than you need 1GHZ(1000 MHZ).
So for a 2 socket quad core system e.g HP380 G5 following could be said:
First CPU 4 x 2930 MHZ
First Core 1 x 2930 MHZ
Second,third, fours Core 0.5 x 2930 MHZ = 1465 MHZ
All Cores for CPU1 = 2930 MHZ + 3 * 1465 MHZ= 7325 MHZ
Second CPU 4 x 2930 MHZ
same as first cpu = 7325 MHZ
So for CPU 1 and CPU 2 we have 14650 MHZ.
Sustract 10 percent for SC and 1000 GHZ for Network than
14650 MHZ - 0.1 x 14650 MHZ - 1000 MHZ = 12185 MHZ are for the vm's.
If you have to garanty 500 MHZ to each VM, than you can have 24 VM'S (12185 MHZ / 500 MHZ = 24,37)
for a two socket quad core system.
