Is it more efficient to use multiple computers when I have multiple GPUs? I have 4 video cards: 2x 7970 &amp; 2x 6970.

This is a question of efficiency regarding MH/s. Simply, I would like to know which is better:


~1900 MH/s on one machine 
~1200 MH/s and ~700 MH/s on respective machines
It does not matter


Could the answer please include efficiency for both solo mining and pool mining?
This is a question of efficiency regarding MH/s. Simply, I would like to know which is better


It doesn't matter. Every hash has an equal probability of finding a block. However, that being said, there's some hidden teeth:


Putting graphics cards together will make them harder to cool.
Putting them in multiple computers will use more electricity - all computers use some electricity, even at idle.



  Could the answer please include efficiency for both solo mining and pool mining?


My advice applies for both.