If you have time, you can watch this video:
https://youtu.be/0domMRFG1Rw
Reference cards usually come with blower style cooler. Other manufacturers can only change the cooling system and the clock speeds of the card - these are the only differences between brands. All the CUDA cores and processing units are the same and the number of them is also the same. The reference card is produced directly by AMD/Nvidia, or in other words, the creator. The thing is that "custom" cards other manufacturers make (msi, zotac, evga, asus..) have better cooling solutions installed which allows to increase card's clock speeds for better performance. That's why custom cards achieve 5-10% better performance than reference cards and stay cooler.
When should you consider a reference card or blower style cooler? Only when your case lacks fans. Blower style cooler takes air from the inside and blows it out from the case, meanwhile other open-air coolers don't blow the air outside, heat stays inside and additional case-fans take care of it. Reference cards are recommended for smaller PC cases with less fans. Photo:
https://i.gyazo.com/3573246899fb475e450fbe40759bbaf7.png
In-depth explanation is in the video.