Apologies if this is in the wrong forum - mods, please move to appropriate one as necessary 
So, I am trying to get my head round host CPU sizing and am confused 
Do I need to worry about number of cores, sockets, logical cores......or do I need to worry about overall speed of the sum of those CPUs?
Example:
I buy a server with 2x 6-core Xeon CPU @ 2.5Ghz, i.e. 2 sockets, 24 logical cores, 60Ghz (24*2.5) total CPU speed.
Let's say I want 6 VMs on this host each requiring 6 vCPUs.....well 6*6=36 and blows the number of logical cores straight away! ...but does this matter?
If each of these 36 vCPUs was running at 1Ghz (made up for this example of course), then that would be just 36Ghz used, with 24Ghz to play with right?
Any help greatly appreciated! 