0dbFS vs 0dbVU, is Cubase Master Meter correct?

A weird thing, we read everywhere about 0dbFS vs -18dbVU. In Cubase, on the Master Fader Meter,
using PSP Free Vintage Meter, 0dbVU on PSP shows as -8.8dbFS on Cubase’s Master Fader Meter.
Isn’t supposed to show -18dbFS or whatever? Am i missing something? Is it correct?
As a test Sound Source i was using Retrologue’s SAW Wave as a constant Wave.

Any help would be appreciate it, my goal is to find the 0dbVU on Cubase’s own meter.
I am on Cubase 6.5.