[gmx-users] testing GROMACS on a cluster of Power4 IBM

[Therese Malliavin]

Dear gmx-users, 

I am testing GROMACS 3.1 on a cluster of Power4 IBM, and I run the demo
'speptide' 
from the tutorial. The unrestrained dynamics was run on 1, 2 and 4
processors 
with the -shuffle option, and I listed below the mean values obtained.
Are the 
differences observed between the runs significant ?

Thank you for your help, 

Thérèse Malliavin
IBPC, CNRS
Paris, France

1 processor:
        <======  ###############  ==>
        <====  A V E R A G E S  ====>
        <==  ###############  ======>
 
   Energies (kJ/mol)
       G96Angle    Proper Dih.  Improper Dih.          LJ-14    
Coulomb-14
    2.73064e+02    1.33075e+02    9.03702e+01    4.32169e+01   
2.21807e+03
        LJ (SR)   Coulomb (SR)      Potential    Kinetic En.   Total
Energy
    5.26205e+03   -4.60253e+04   -3.80055e+04    6.91378e+03  
-3.10917e+04
    Temperature Pressure (bar)
    3.03590e+02   -2.01513e+01

2 processors:
        <======  ###############  ==>
        <====  A V E R A G E S  ====>
        <==  ###############  ======>
 
   Energies (kJ/mol)
       G96Angle    Proper Dih.  Improper Dih.          LJ-14    
Coulomb-14
    2.80620e+02    1.35959e+02    8.55556e+01    4.67056e+01   
2.24677e+03
        LJ (SR)   Coulomb (SR)      Potential    Kinetic En.   Total
Energy
    5.28656e+03   -4.60615e+04   -3.79793e+04    6.91485e+03  
-3.10644e+04
    Temperature Pressure (bar)
    3.03636e+02   -1.69452e+01

4 processors:
        <======  ###############  ==>
        <====  A V E R A G E S  ====>
        <==  ###############  ======>
 
   Energies (kJ/mol)
       G96Angle    Proper Dih.  Improper Dih.          LJ-14    
Coulomb-14
    2.73248e+02    1.29288e+02    8.55897e+01    4.46836e+01   
2.21640e+03
        LJ (SR)   Coulomb (SR)      Potential    Kinetic En.   Total
Energy
    5.29161e+03   -4.60257e+04   -3.79848e+04    6.91265e+03  
-3.10722e+04
    Temperature Pressure (bar)
    3.03540e+02   -3.98152e+00