Floyd Mayweather -- My New Hyper Car Drives Paris Hilton Wild

If Floyd Mayweather is the master of self-promotion, Paris Hilton is the mistress -- and she used Floyd's purchase of a super rare $4.8 mil hyper car to let the world know her BF is super rich too.

Floyd's new whip -- a Koenigsegg CCXR Trevita -- has been all over social media since he picked it up over the weekend, and BSO pointed out it's also on Paris Hilton's radar.

Actually, P kinda shouted it from her Ibiza rooftop, tweeting Floyd (and her 13 million followers) that her multi-millionaire piece, Thomas Gross, has the only other CCXR ever sold.

You know the only thing Floyd's thinking now, right? Who got it first??!!