well, i havent see the card by myself, but it still have 2 years warranty by Gigabyte, he said it never been overclocked, the price difference between the new and used gtx 680 is around IDR 2.000.000 ~ USD 200 in this case.
my current PC spec :
motherboard: asrock z77 extreame 6,
intel i53570k,
2 x 4gb ddr3(corsair),
nvidia gts250 by DA
PSU 500 watt (they said it's "pure", tough i dont know what it means)
the PSU is irrelevant because either way i need to buy new one
any idea what should i seek when inspecting the card? cause you said something is fishy..
i could use the heads up