I have a strange problem with my smp-system. Hardware config: Tyan s2895 mobo, 2x Opteron 270 Dual-Core CPU, 16GB ECC Reg. RAM We use this Workstation for CFD-Analyses. When I start 4 Jobs on 4 CPUs, at least 2 jobs die (segmentation fault). One job works fine. A parallel run using mpich as MPI aborts (Error message says that it has recieved a SIGABORT signal form a CPU / SIGSEGV). The strage thing: If I remove 8GB of RAM, the system works stable. Neither an update from Suse 9 to Suse 10 nor a manual compiled kernel with the current stable version helped. A memtest86+ showed no errors (running 5 days), so I think that a bad RAM module is not hte reason. Furthermore, a cpu-stress test with cpuburn-in worked well (24 hours running without any errors). Might be a problem with the memory managment? Any hints how I can resolve my problem? Christian