[gmx-users] pressure coupling

[kiana moghaddam]

Dear GMX Users

I have encountered with the following warning during NPT simulation of DNA-ligand interaction by Parrinello-Rahman pressure coupling (ref_p: 1bar).

WARNING 1:

You are generating velocities so I am assuming you are equilibrating a system. You are using Parrinello-Rahman pressure coupling, but this can be unstable for equilibration. If your system crashes, try equilibrating first with Berendsen pressure coupling. If you are not equilibrating the   system, you can probably ignore this warning.

After that, I used Berendsen pressure coupling without any warning. Pressure fluctuations were between -1000-1000 bar. There are 730 atoms and 13071 waters in my system. 
Although I didn't get any warning, I'm not sure that the Berendsen coupling and Pressure fluctuations for this system is correct?

Please help me

Best Regards
kiana