I have two identical systems. Both Running AMD Sempron 3600+ processors on an ASUS M2V-MX boards. Only difference lies in the memory. One had 1GB the other has 1.5GB. The system with 1.5GB is using 97% memory. 79% of that is cache. The system with less memory is using 21% memory, of that, 4% is cache. Both systems are identical in their system configs.. I have no idea what could be causing such a drastic difference.