[gmx-users] REMD speed calculation compared to classical MD

[ABEL Stephane 175950]

Dear All,
 
For a futur project, I would like to perform the REMD calculations with GROMACS4.5.X. To have an estimation of CPU time required, I have a naive question: What is the speed of REMD compared to a classic NPT MD ? I am aware that the response depends a lot of factor (number of replica, etc.), but since i have no idea and experience with this type of MD, I ask the question ;). 
 
The system will have approximatively 25000 atoms. Previously for this system, I got 11 ns/day on 32 CPU for a NPT MD with GROMOS53A6 and GMX4.0.5.
 
Thanks you in advance for your response. 
 
Stefane