Jun 03 18:40 2014, Joe Delahaye wrote to Markus Reschke:
JD> It seems that it can be worse. Open WRT for my TPLink model AC1750, JD> will not JD> support the 5 Ghz protocol. Only the 2.4 side. Should have JD> purchased the JD> cheaper model it looks like. Also, I was having problems staying
For the Archer C7 v1.x and WDR7500 v2.x, the 5GHz 802.11a/n/ac functionality is not supported, and likely will never be, since support for the AR1A (v1) variant of QCA9880 chip is not included in the open source ath10k driver. The Archer C7 v2.x uses the BR4A (v2) variant which is supported in ath10k.
The 5GHz module seems to be a Mini PCIe. So you could replace it with something supported, but would have to add the driver manually, I assume. If that's too much hassle, the TL-WDR4300 (about EUR 50) is fully supported and got also dual band.