I suggest you check your setup and confirming that everything is ok before getting any additional items.
Strip everything out of your casing and place it on the table or some non-electrically conductive place to conduct a power on.
I have encounted motherboard leads at the bottom of the PCB that is close or touching the PC casing causing errors and other problems. It is difficult to catch as it is intemittent and not directly visable.
As you have encounter the same failure twice, it might be due to some fault somewhere. You might also want to check your power cord(might be poor contact), your home electrical layout leading to your computer power point for faults. Check your ground points for proper grounding.
Do all the checks first before committing to an additonal equipment as it might be quite unlikely to be cause by electrical surges...