The ASUS ROG STRIX X870-A GAMING WIFI wins in 6 out of 14 comparable specs, with 7 ties. Its biggest advantage is Max Memory (33% better).
MAG B760 TOMAHAWK WIFI wins in 1 spec (MSRP: 40% better).
Recommendation
Choose ROG STRIX X870-A GAMING WIFI if you want the best overall performance — especially max memory.
Choose MAG B760 TOMAHAWK WIFI if msrp matters more to you.
