im currently trying to overclock my gtx 280

and was wondering what would be the best test, to do to see if it is stable.
i am currently using 3dmark 06 and the temps are fine etc not getting any issue's, at all my scores are increasing

but i would like to know if there is anything better than 3dmark 06 to stress the gpu to see if it is stable or not.
cooling should not be a issue as i have it watercooled with the card on its own water loop connected to a dual radiator, temps at the moment are not going above 55c when running 3dmark 06.
---------- Post added at 15:33 ---------- Previous post was at 15:26 ----------
also i am now hitting some quite high speeds core at over 700mhz from stock of 615mhz, still running fine.
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