WiFi connection slower on Windows 7 (Intel 7260) but faster on OS X

[ICust20]

Let me state the problem. My ISP provides a 60mbps connection to my place. The router is set to abgn mode (to support older devices to) and runs on 2.4GHz.

I've got few devices that are connected to that network and some of them do support at least 802.11n standard. Below are speedtest results for them:

1. http://www.speedtest.net/my-result/3362212217 MacBook Pro with Mavericks
2. http://www.speedtest.net/my-result/3362217357 PC with Win7x64 (Intel DualBand Wireless AC 7260 on-board adapter) - WLan card integrated with Gigabyte GA-H87N-WIFI mobo

There's no way I could get anywhere near the speeds of my Mac on my PC if it comes to the connection. It's always around 20mbps. I did try with different USB WiFi cards (both from TPLink in 802.11n standard) but it was the same.

Any ideas?

[Jose_H_Intel1]

May I suggest testing the system in safe mode with networking? I guess there is some kind of software issue or perhaps interference that only affects this system.

[tvete]

Try these articles:

http://www.intel.com/support/wireless/sb/CS-030709.htm Wireless Networking — What are the recommended settings for 802.11n connectivity?

http://www.intel.com/support/wireless/wlan/4965agn/sb/cs-025643.htm Intel WiFi Products — Data rate will not exceed 54 Mbps when WEP or TKIP encryption is configured

http://www.intel.com/support/wireless/wlan/4965agn/sb/CS-028449.htm Wireless Networking — How do I improve my 802.11n wireless performance?