bug check

Hey guys, Issue my computer came up with mid-game was: The computer has rebooted from a bugcheck. The bugcheck was: 0x0000003b (0x00000000c0000005, 0xfffff8043f673e0b, 0xffffa1818c36e3b0, 0x0000000000000000). Just installed 2 more sticks of RAM, from 2 to 4, with a different brand to what was...