Guild Wars 2

In the past two months, everytime I boot up GW2 and get into the game, literally just past loading my character, I crash completely on my computer. The game gives me no warning, my system just completely goes into shut down mode and then reboots. I’ve had this computer set up for over 2 years, with minimal problems playing GW2 on it. I get laggy occasionally, and have the entire game running on best performance.
My set up:
Windows 7 Professional
AMD FX-8350 Black ED
Gigabyte GA-990 FXA
Coolmast Hyper TX3 Universal CPU
Corsair 750W CXMOD 80
(I’m not great with computers, just going off of the original receipt from 2013).

General question about Striking off the Chains personal story quest. I couldn’t find it posted on the forums.
When I go to battle the Priestess at the top of the tower, I set up a net turret, flame turret, and summon Mistfire Wolves asap. Note that I play an engineer, level 63. Is the Priestess still able to summon Krait when she is immobilized for seconds at a time? Also when I’m in ‘Fight to Survive’ and kill an enemy in this section, I never go back to normal battle mode, and I’m not sure if my game is bugged since I’m having massive issues with this quest. Any advice/help is appreciated!