The research activity of the Laboratory of Computational Chemistry and Biochemistry (LCBC) at the EPFL focuses on the development and the application of first-principles and mixed quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) methods based on density functional and time-dependent density functional theory. The group's central codes are CPU, memory and communication intensive. LCBC was formed in 2002 and typically consist of 15-20 members. As the group is involved in purely theoretical and computational research, sufficient local computational resources are absolutely essential for our work. The group's local computer clusters are now 3-4 years old and have to be renewed.Here, we propose to replace the old 4-node high memory machines with six 2x quad-core AMD Opteron 2384 with 32 GB memory and 2.7 GHz processors, and the 64-CPU-medium memory-Myrinet cluster with 21 twin nodes 4 x quad-core AMD Opteron 2384 with 16 GB memory, 2.7 GHz processors and Infiniband interconnect. The total cost for the renewal of the computational equipment amounts to 237k SFr. We request 50% (118.5k SFr) from the R'equip programme of the SNF and the other 50% from EPFL as a matching fund.Since LCBC is involved in many collaborations with experimental groups, e.g. within EPFL we are performing calculations for projects with the groups of Majed Chergui, Paul Dyson, Michael Graetzel, Vassily Hatzimanikatis, Hilal Lashuel, Kay Severin, Thomas Rizzo, and Horst Vogel, several groups at the EPFL will indirectly profit from this acquisition too.