[MetalMilitia]

9 times out of 10 a dogey reading from the motherboard temperature sensor is down to the bios. Although I would suggest using 'Speedfan' to show temperatures as it has always worked best for me, and everyone else I know.

As for the issues of higher GFX card temps, while it *should* be fine so long as you are not seeing any artifacts or vertex corruption you should understand that it may reduce the life of your card. However, as an 'enthusiast' you'll most probably change the card long before this becomes and issue.