Hi Rarefiedgrit

Have a look at the link below regarding the cooling system of your motherboard.
As Kemical has suggested, temps. are important when overclocking has taken place. Although you say the temps. are o.k. and the case is well ventilated you need to get some figures to check that out.

Note the special chipset cooling fan in the link below:

eVGA nForce 680i SE SLI Review - hosted by Neoseeker


Its worthwhile looking through all this review as it mentions cooling systems in detail!!!!!