eap authentication and cpu utilization

[Norbert Wegener]

Simple authentication with login/password can be handled in  large 
numbers with a recent cpu and freeradius.
.
EAP authentication on the other hand requires a great amount of cpu 
processing.
Therefore I have  a simple(?) question:
Did someone already calcute the theoretically maximum number of eap 
authentications per second, that a recent x86 cpu is able to handle?
Or did someone some practical research on that issue?

Norbert Wegener