Try niyo po na palitan yung PSU
Kung bibili man po kayo ng bago, paki-check na lang yung brand sa LTT PSU Tier List para decent yung makuha niyo po TS.
Power supply muna TS.. tapos obserbahan mo muna kung may pagbabago.. if ganun pa rin, nagrerestart palagi, try mo naman yung video card mo... (drivers) or hardware... nacheck mo naman yung memory e,, kaya ignore mo na yung memory.. step by step ka muna.. (power supply, video card, memory, hdisk or motherboard, or Operating System or Drivers).. yan lahat icheck mo.. ewan ko lang kung sasablay ka pa dyan.. hehehe.. gudluck TS.