Different solutions using restart

Hello all-
 
I was curious if anyone else has experienced conflicting results using the *restart command in abaqus explicit (ver 6.7 - 6.8).  For example, differences that exist when comparing results for a particular analysis evaluated in two different ways: 1) with several small steps using the restart command between steps and 2) using a single step for the entire analysis.  Is it possible that there is some "round-off" error induced by writing the state of the model then reloading it, or might there be some aspects of the state of the model which are not conserved using restart?  Any related experiences would be appreciated.
 
 
Thanks in advance,
Chadd Clary
 
Post-Doctoral Research Associate
University of Denver