for real? strange. its it allot of dots? The dots show up long before any game will error so it may or may not be safe to go on. I personally would not, but its your call. I think Evga has a lifetime warranty on cards(as long as they do not know you had been overclocking)
I have run hours of it on my 8800GTX without any errors.
I guess your method will be small increase, games or 3d marks and repeat. Still every card is different for its max.