Sounds like hardware to me.. Either the ram or the motherboard. Modern motherboards have built-in obsolecence. Take a look at the electrolytic capacitors (vertical cylinder-shaped thingies with 3 converging lines on top). If the top looks like it's bulging (should be flat), or there is some brown stuff on top, the capacitor is defective. You can either try replacing it (good luck!) or get a new motherboard.