Massive graphics issue
Could be overheating, check your temps. You should also clean out the dust in the vents to prevent. If that fails you can try to repair the client https://help.guildwars2.com/entries/28148006-Repairing-the-Game-Client
There are aftermarket laptop coolers available as well for a low price
i7 3770k oc 4.5 H100i(push/pull) 8gb Corsair Dominator Asus P877V-LK
intel 335 180gb/intel 320 160gb WD 3TB Gigabyte GTX G1 970 XFX XXX750W HAF 932
intel 335 180gb/intel 320 160gb WD 3TB Gigabyte GTX G1 970 XFX XXX750W HAF 932
Thanks. I had to re-install the game, that helped.