Been lvling up my triple paladin group, taking on sunken temple.

up to now, the group has been going well and my computer seems to be handling triple boxing on one machine quite fine. triple boxed wc, sfk, rfk, sm, rfd, ulda, zf, mara well and easily took them down.

but tonight when I was going through ST, killing the trolls just before Jammal'an, one of the mobs feared my main. but as soon as that mobs spell cast ended, my computer froze... restarted the computer to find i had to start ST from scratch =/

but anywho, main question I wanted to ask, (and this is something i noticed back when i was only playing one box) is; is there a reason why my computer slows down when i get feared? and then when i'm triple boxing, being feared crashes my computer? I think this is actually the first time my main got feared since i started triple boxing, so now am kinda worried...

anywho, any opinion would be greatly appreciated.