I have the same problem and it's getting real worse in last week or so. The only difference is my PC not a laptop, it's a desktop.Sorry for my english (not my native) but i'll try to discribe it in short story : i've been playing GW2 for several years (not every day and without long breaks ofc, but pretty much often overall) and all this time i'm using the same machine for it. And the only major and significant things i've changed in that PC was GPUs and OS. Started to play GW2 on Windows 7 with MSI GTX770 Gaming (factory OC only) - > not a single system shutdown/restart for all time.Then change it to Windows 10 and MSI GTX980 Gaming (factory OC too and i haven't been OC anythin' there) -> same. Not a single shutdown for a year and a half.Then changed it to GIGABYTE GTX1060 (6GB) (with factory OC + i've OC'ed it slightly) -> experienced my first BSODs and restart in GW2 as soon as i try to play with it. Changed back my OC settings down a little (but not downclocked or disabled it), found some stable one, tested it and played GW2 without problems after (1 year) So, yeah, game is "sensitive" to even slight overclock. And finnaly, around 2 weeks ago or so i've changed my GPU to MSI GTX1080 GAMING (factory OC, not OC'ed anythin' manually) and got the same problems as author discribed in this thread : at any place, at any time, absolutely random, without any BSOD my PC locks up and restarting. It may happen after couple of hours in GW2 or just after i'm logs in. In crowded area or in solo-instance. Or may never happen for may hours or days. After today's Haloween update my game crashed and restarted PC twice already. It happens ONLY in GW2. Temps is absolutely normal on all components. So it's not overheating for sure. Playing any other games old and new for hours and hours and never seen a single problem/crash/hardrestart (playing new Shadow of Mordor and Evil Within 2 atm), working and building/rendering heavy scenes in 3D's Max and other programs and it's completely fine too. Making stress-tests and both GPU and CPU works absolutely fine with it. So it happens only with GW2. Checked it with GPU-Z and it shows that GPU Clock is 1620 MHz and Memory Clock is 1251 MHz. Should i downclock it and test? And i'm not sure how to downclock somethin'. I know how to OC slightly with Afterburner ofc but never needed to downclock anythin' lol. How to do it? I see several recent threads here about similar issue and all people says it's getting real bad after some new game's update at the end of september or smthn. But my problem that i've changed my GPU around this time and cannot say for sure what caused it for me. Current rig : i7-4790k (not OC)/ MSI GTX1080 Gaming/ 16GB RAM/ Win10/ PSU Corsair CX 750W