Which would run better? That has a greater chance of overclocking ? Better warranty customer service ? lol I wanna purchase by today. Please let me know
Out of the box the Gigabyte GV-N670OC-2GD is faster than the ASUS GeForce GTX 670-DC2-2GD5 since the ASUS card uses nVIDIA's reference clocks.
Overclocking potential? I would have to say the Gigabyte GV-N670OC-2GD because its operating temperature is lower.
In a review of the Gigabyte GV-N670OC-2GD, that I've read, they were able to overclock it higher than the ASUS GeForce GTX 670 Direct CU II TOP GTX670-DC2T-2GD5 could be overclocked (the ASUS GTX670-DC2T-2GD5 is the factory overclocked version of the ASUS reference clocked card you linked to).
Your experience may be different since overclocking potential is not consistent and is based on if you're lucky enough to get a card that has a high quality ASIC (i.e. GPU chip)
They both have the same 3 Year warranty period. I've heard of bad customer service from both companies although I've heard that Gigabyte's is worse than ASUS'.