Try readings from coretemp.
The lower the temps the better.
In winter my E6600 idles at 19-22 degrees celcious at stock voltages. If your readings are under 30 and you get an error due to temps then there must be an problem either with the sensor or the program you are using
That's the only reason I wish I bought a Core2 rather than my i7. So far this summer, on a hot day, my i7 IDLES at 41c...
Of course it's overclocked rather nicely but still.
OP go to google and type in RealTemp and download the program. Open it up and leave it open while you play your game. Play for at least 10 minutes then exit out. Once out you should have some good temp information. Take a screenshot and post it here if you can.