Guild Wars 2

Personally I have had a bad experience with upgrading Win7 to WinX. A fresh clean install sorted out all the issues I had. If I were you I would make sure that ALL drivers are updated for WinX e.g. soundcard, ethernet, wifi etc. Also use DDU to properly uninstall your GPU drivers and freshly install the latest ones for your graphics card. If you have an Nvidia GPU DO NOT install the latest Nvidia drivers as they seem to cause some issues. Try a previous driver version. If nothing works I would just proceed with a fresh clean install of WinX on your system.

Hope I have helped a bit.

Have you checked which GPU your system is using when you launch GW2?

I downloaded the 64bit client yesterday and it has been working flawlessly. I was experiencing random disconnects at least twice a day with the 32bit client but ever since I started launching the new client I have had no such issues.

Cpu: Intel i5 4460 3.20Ghz
Ram: 8GB Corsair Vengeance DDR3 1600Mhz
SSD: Samsung 850 PRO 256GB
GPU: Sapphire R9 380 4GB [factory clocked]

Firewall/router exceptions added.