NBU MSDP Media Server kept on rebooting intermittently.

Friends,

I have got strange problem going where one of my media server keep on rebooting mostly over the weekend.

OS SuSe Linux 11 SP2

NBU 7.6.0.3

Physical box HP DL180 G6

Its an onsite appliance that backs up client locally and replicate (AIR) to central location. 

/var/log/messages doesn't contain much information..

I have ran the HP diagnostic to see if there are any problem with hardware componenets but all came out. 

I have upgraded the FW and number of drivers and due to upgrade BIOS but i dont think abnormal reboot has anything to do with BIOS. 

Has anyone seen this problem. any input/ideas will highly be appreicated otherwise i would have no choice except to rebuilt the server.