mac vs windows

What in the past and the present has this been ( windows pc , vs Mac ) .. I would imagine Mac being hotter in temps.. since windows pc has water cooling / big heatsinks , bigger Cases and fans , and Mac is Usally Smaller ( im not Talking about laptops, but if you want to below, you can :-D...

I have never had a an issue with my HP Pavilion G6 for years now but I would like to change the fan out since it is making noise for a few minutes at start up, then goes quite, probably dirt as all I ever did for 4 years is blow it out with an air compressor. And have read a lot about all this...