Tomshardware benchmarked this question years ago and came up with about ONE PER CENT changes from board to board and chipsets. They kept the same CPU, RAM and GPU and the result was there is rarely a per cent point change in performance. The changes were so low that they called it human or measurement error.
That said, I'd go with the newest chipset after I google to see if anyone is complaining in volume about that chipset.
Which chipset would be better with a Ryzen 7 2700? I've made list of x370, b450 and x470 boards that seem to have a great performance for gaming, and still fit my budget.
x370
- GIGABYTE X370 GA-AX370-GAMING K3 (US$185.19)
b450
- ASUS PRIME B450-PLUS (US$187.63)
- MSI B450 TOMAHAWK (US$190.10)
x470
- ASROCK X470 MASTER SLI (US$217.26)
- GIGABYTE X470 AORUS ULTRA GAMING (US$244.43)
- MSI X470 GAMING PLUS (US246.90)
- ASUS ROG STRIX X470-F GAMING (US$246.90)
As far as I've been searching, it looks like the b450 is enough for the R7 2700, even making overclocking possible, obviously without the same results as the x470s. Besides, the performance difference isn't worth the price difference.
Things I forgot to mention:
* All prices have been converted from brl (brazilian Real) to usd. That's why they may look weird.
* I do not plan to overclock the 2700 to its maximum, so much that I will keep the stock cooler.
* My budget's limit is the ASUS ROG STRIX X470-F GAMING (considering prices in Brazil).

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