Connecting 802.11ac laptop to wireless network causes other devices to disconnect

[AW6]

I have a b/g/n tplink wireless router set up with WPA2 security and DHCP enabled. I have several devices connected to it. The laptops (all win7) have b/g/n network cards. However, when I connect the problem laptop (let's label it the ASUS, it has an Intel dual band AC 7260 network card, win8.1) to the network, all other devices lose internet access and/or disconnect from the wireless network. Turning off the ASUS wireless and power cycling the router will restore network connection and internet access to the other devices. I have updated the firmware on the router (published 5/2013) and Intel wireless software/drivers but still have the disconnection issue. Any input on this situation would be greatly appreciated, thank you!

[tvete · Accepted solution]

Try disabling U-APSD support on 7260's settings and see if it still makes the router drop WiFi.

[AW6]

That seems to have done it. Thank you so much. The connection is no longer dropping on any of the other laptops.

Is the U-APSD support a necessary function? In other words will wireless connection be alright functionally and performance wise to just leave it disabled?

[tvete]

U-APSD does not affect any connection performance and stability at all. If implemented CORRECTLY, U-APSD should improve battery life while having all the speed the WiFi can get (analogous to Intel SpeedStep technology). However, some routers can't implement this feature correctly resulting to the issue you're having or sometimes speeds just slows to a crawl.

See article here: http://www.intel.com/support/wireless/wlan/sb/CS-025393.htm Intel® Wi-Fi Products — What are the advanced Wi-Fi adapter settings?