Logic Board or Internal Power Button Problem

After pressing my power button, my MBP now starts and cuts off before booting, also cuts off sometimes while booting up and sometimes take four or five attempts to boot up the laptop.

However, when my MBP finally maintains power after pushing the power button and boots up…ALL SYSTEMS AND PROGRAMS AND GRAPHICS WORK. The MPB never shuts off after it is started It does [lock up] sometimes when it goes to sleep>then requires a power off then power on restart AND then boots up on first try after previous session

My laptop has been very well taken care of since 2009 purchase. Never dropped, no water damage ever, etc!

So, is this a logic board or internal power button problem?

Thanks everyone!