I don’t know how “pure” you want your chiptunes to be, but for my money Master Boot Record is some of the best stuff out there. I would definitely say it’s at the very least gaming inspired if not pure chiptunes, and it kicks all kinds of ass. They’ve done a lot of covers of classic game music - Bloody Tears is a great one, as well as their cover of the Doom theme. But I really love their original stuff too. Internet Protocol is a 10/10 album to me.
Slightly less chiptunes but still absolutely gaming inspired is their side project Keygen Church. Tenebre Rosso Sangue from the Ultrakill soundtrack is probably their best known track. It’s sort of a chiptunes adjacent castlevania-metal vibe? It’s hard to describe but it absolutely destroys.