Been having more problems with the computer hard shutting down playing GW2, so I fired up RealTemp and it is showing that all 4 cores on my I-5 (stock cooler and speeds) have had a thermal throttling episode logged. Never had any issues playing anything else. The Grove seems particular bad for triggering it. Graphics settings are auto-detect but I have noticed that there is a drop-down in the options to limit the frame rate which has unlimited as default, so I’ll give it another go tomorrow with that set to an actual value.