Try this 1
Remove the RAM from the slot, clean it and place it back properly or try another
slot. Check the RAM also to make sure that it working properly. You can check
your RAM using memtest86+ application. You can download it from the below link.
Download the ISO file --> Burn that to the CD and boot from it by setting the
first boot device as "CD\DVD drive".
It's a continuous loop process so try few pass to detect the errors.