suse 9.3 system reboot on large scp/rsync >3GB

Whenever I scp or rsync a large amount of data (>3GB) the system suddenly reboots. The system runs Suse 9.3 (fully updated) . When the system is rebooting from an attempted rsync or scp it displays that dimms 5 and 6 are both bad. I have 12GB total. 5 and 6 are 2 gig dimms from Crucial. I would do a Ctrl+Alt+Del at this point the system comes back normal. I've also reseated the RAM but the results are the same. Has anyone experienced this at all or may know what's going on? TIA. --ryan