I was working on my Pavilion laptop when a barely discernable popping noise seemed to emanate from inside the laptop. Simultaneously, it lost power. Subsequent attempts to power on, including the remedy of removing battery and charge cord while holding power button down for 30+ seconds; failed to produce positive results. Tested the power cord on a 2nd Pavilion I own and it is fine. The battery appeared to be a bit swollen on 1 side. Purchased a new battery. Still won't power on at all. No lights, nada. My limited knowledge tells me this is likely the motherboard crashing. Seeking expert guidance. Thanks.