I'm pretty sure it's a problem with the Intel 7260 wifi module. I ended up installing Ubuntu Linux (13.10) because I was experiencing wifi problems in Windows - the connection would drop quite often, and the speed would slow to a crawl before stopping completely. Completely unusable.
I decided to install Linux. Unfortunately I was still experiencing the same wifi issues with the Intel 7260 in Linux. I did some Googling and read about the issue with the Intel 7260 wifi module. A workaround is to disable 802.11n. My connection no longer drops, but my bandwidth has dropped from around 9MB/s to 2MB/s. Disappointing, but at least I can now watch YouTube or maintain an SSH session without dropouts/freezing.
If you want to try this on your unit:
On Windows:
1. Open Control Panel | System Security | System.
2. Open Device Manager on the left hand side of the window.
3. Click on Network Adapters.
4. Right-click on Intel Wireless 7260, and click on properties.
5. Click on Advanced Tab.
6. Click on HT Mode and then select disable.
On Linux:
1. Open terminal.
2. sudo vi /etc/modprobe.d/wifi-disable11n.conf
3. Add this line: options iwlwifi 11n_disable=1
4. Save and restart.
Intel claim they have a fix: http://www.intel.com/support/wireless/wlan/sb/CS-034535.htm
This did not work for me.
HP have released a defective product (by including a defective Intel component).
Please post back here and let me know how you get on.