Nearly every single AC7XXX cards have issues. I just got a new PC, using the AC 7265 Wifi Card and I get constant package loss while gaming. This was the same experience with my old 7260 as well. Online is the same story.
This happens in Windows 10. A solution has not been made for a long time. Why hasn't Intel found a solution for this? This is beyond frustrating.
We recommend that you contact your computer manufacturer: http://www.intel.com/support/wireless/sb/CS-006192.htm Wireless Networking — Installation Error when Installing or Swapping Intel Wireless Adapters and check for the latest drivers updates for your wireless adapter.
As a second option, you can use our latest drivers found here: https://downloadcenter.intel.com/product/83635/Intel-Dual-Band-Wireless-AC-7265 Downloads for Intel® Dual Band Wireless-AC 7265 - Please, make sure to download the drivers according to your system architecture (32 or 64 bit). You can also do the following that might improve your connectivity.
1 - Change the channel on the router to a less crowded one.
2 - Close all other applications that could be using internet in the background if their use are not necessary at the moment you are playing the game.
3 - Optimize your connection:
Disabling Bluetooth* if its use is not necessary may improve your connection as well as it shares the same antennas used by Wi-Fi. Specifically for gaming, enabling WMM on the router may improve the connection as well.
Focusing on the packet loss while gaming. I used to play online games a lot and I myself have experienced it from time to time. There are some online games that are really finicky and often use UDP (User Datagram Protocol) for a lot of features to send and receice packets. UDP, unlikely TCP (Transmission Control Protocal) is generally unreliable and makes no guarantee whatsoever that the packet will be delivered, while TCP, on the other hand, will deliver all packets in order, unless, of course, the client disconnects. UDP does not reliably check for disconnects, so instead, you may rely on a "timeout" check, if any. Once the server or client doesn't hear from the other for a certain amount of time, it assumes that you have disconnected and tries to re-establish a connection with the opposite side. As you may know, certain games demmand extremely high traffic and UDP has a tendency to drop packets when the traffic gets extremely high.
A lot of online game players use this site: http://www.pingtest.net/ Pingtest.net - The Global Broadband Quality Test - (*NOTE: This link is being offered for your convenience and should not be viewed as an endorsement by Intel of the content, products, or services offered there) in order to check the the quality of the connection and this test will give you three very important factors about your connection quality.
Latency - The time it takes for a packet to eb sent and a response to be retrieved. An optimal latency for certain games is between 30 and 125ms (milliseconds). Anything higher that that will introduce noticeable lag and possibly packet loss caused by the system getting clots of packets at once and sicarding some to avoid blocking.
Packet Loss - Inherently caused by high latency, but also caused by upstream/downstream issues with the ISP and also checking the network setup such as the hard connections (faulty cables etc...)
Jitter - This is the inconsistency between the travel times (latency) of each packet. Generally, it should take approximately the same time (give or take a few milliseconds) for each packet to travel out and for a response to come back in. If your jitter is higher than around 15 to 25ms, you will see problems when playing certain games. You cna play with the jitter value as high as 100ms, but slight issues can be noticed. Jitter is another indicator of problems with network setup and, again, could be caused by anything from the ISP to wiring...etc.