Are you getting any message after or before the system restart?
When the problems start? Did you make any hardware or software aggregation that could be related with the problem?
What is the operating system?
How long the system last before restart?
Do you see any fan or light activity before or after restart?
Clear CMOS battery taking it out for 5 minutes, then put it back or go to the BIOS and load the default settings with F9 then F10.
Check the memory specifications for each board. Voltages and frequency.
Test the system with basic configuration (1 memory stick, not CD&DVD only 1 hard drive with the OS)
Check 1 memory stick at the time on the blue DIMM closer to the processor, to confirm each one of them is good.
Try to test the system outside of the chassis as you could be facing a grounding problem between board and case.
Try to update the BIOS with the latest version.
Thanks for your response. Please find below the answer of your query,
When the problems start? - 03 days after configuration of the system
Did you make any hardware or software aggregation that could be related with the problem? - No.
What is the operating system? - Windows7 Professional.
How long the system last before restart? NA
Do you see any fan or light activity before or after restart? - Yes, Fan is working as normal.
I have done all the steps given by you. But issue is still persist.
Kindly look into the matter and do the needful as soon as possible.
Try to test the system in maintenance mode:
1) Turn the system off
2) Set the system with basic configuration
3) Move BIOS jumper to position 2 and 3 (sets the system in maintenance)
4) Turn the system on and it should go to the BIOS screen automatically
5) Let the system in BIOS for a couple of hours, so you make sure it is stable (no restarts )
If the system restarts, even in the BIOS screen it might be a problem with the board and if that is the case, check warranty options with your place of purchase.