What math? Did Greg specifically say they are supposed to give 8m EU at some point?
Plasma cells only generate 4096k EU each. This is even stated in the NEI tooltip.
http://gregtechcommunitywiki.wikispaces.com/Plasma+Generator - 8192k
http://ftbwiki.org/Plasma_Generator - 8192k (Yes it's for pre 4.0 but I see no mention of change from 3.0 to 4.0 notes from Greg)
What NEI tooltip are you referring to? My NEI tooltip does not state the amount of energy the plasma cells generate. Can you tell me how to turn on this feature?
I now see the tooltip stating that they only generate 4096k EU. Does anyone know when this change was made?
In in addition to the lower total output, you can only run 16 plasma generators total with this equation. I have been using Gregtech for awhile and I'm pretty sure I've always been able to run at least 32 since v2.82c.