Question about ASUS Pce-Ac56

Yes, this is possible. The adapter supports the 2.4GHz and 5GHz frequency range.

Enclosed is a small overview between 2.4GHz and 5GHz:

2.4 GHz WLAN network:

Longer range
More susceptible to interference, as technologies such as Bluetooth also use this frequency.
Very widespread. There may therefore be overlaps with the WLAN networks of neighbours.
Slower than the 5 GHz WLAN network

5 GHz WLAN network:

Slightly shorter range
More interference-free and therefore faster, especially over short distances
Less widespread
Ideal for bandwidth-intensive applications such as video transmission

ASUS G30AB (Intel Core i7-4770K, 32GB, SSD, HDD)
I have this PC. The only thing that has changed is the graphics card. The new one is an Asus GTX 970 Strix.