nMP gaming heat in Win vs OSX

Anyone else experiencing this? First time I'm playing games on a PC in 15 year, so this might be perfectly normal?

Playing BF4 in Windows (HD resolution, Ultra) brings the fan to max and nMP gets scary hot. (Tried without Crossfire... slightly cooler)
Tomb Raider in OSX (4K resolution, Ultra) quiet as a mouse, lukewarm.
Skyrim in HD resolution through VmWare Fusion, lukewarm and silent.