Macbook 13" shuts down randomly. Too hot? DJing in Serato

I just had my Logic Board replaced on my Macbook 13" recently and tonight after DJing in a hot basement for for a little over an hour, it just SHUT OFF completely. I restarted it and it played again for a minute and shut off again. I figured it was hot, since there were a lot of people and hardly any outside air flow. I got a fan from a cooler source of air and cooled my laptop off... Regardless of how cool my laptop got, it still would shut off.

My computer is about 6 years old, but it has a brand new Logic Board from Apple.

I did reset the PRAM if that helps at all.. The computer is completely up to date with software updates.

Am I missing something? I did see this thread, but wasn't sure if it pertained to me.

http://support.apple.com/kb/TS1599

Thanks!