We've certainly seen reports of USB incompatibilities with the M5A99X EVO but these reports are mostly from the 2016 launch window so it's not something there's not really a wealth of recent data points on this MoBo. There are definitely some anecdotal stories of people resolving their USB issues by getting a new controller in combo with this MoBo. We mostly see reports about the z170 as it's more common.
I would say that it's certainly possible for the USB ports on Asus motherboards to be incompatible as they're often running a controller system called Asusmedia rather than letting the CPU act as the host.
The only USB card we recommend is from the brand Inateck - they've proven to be the most reliable USB controllers with Vive/Valve hardware. This card is known to be compatible with Vive and is on the affordable end of the PC hardware spectrum.
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