mine does the same, exept i see graphical glitches that get worse as time goes by before my computer locks up...its murder at the character selection screen..i can probly get away with 3 mins on that screen until textures flicker from green to white to red to texture etc getting faster with more "faces" flickering.
my computer is fine, it runs everything else perfectly without hesitating and used to do the same with eq2.
since the new update its messed with something. looks to me like a memory leak