dafatha00: I doubt it is the memory... try benchmarking the memory with something like Sandra's SIMM, DIMM & RIMM SPD EEPROM Analyser to determine the actual specs of your memory...
I am sure it is probably some other factor of your system... what chipset you using? mobo? It is possible that it is the memory, but I higly doubt it... this mem is rated cas2 and I have seen excellent performace from it while running at 133 2,2,2 @ 1000MHz...