Galaxy went all out on the GTX 670 GC, using a full length custom PCB which allowed them to overclock the card by almost 100MHz right out of the box.  The base clock is 1006MHz as opposed to 915MHz and is higher than the stock boost speed of 980MHz, the GC’s boost pushes all the way to 1085MHz.  Memory size remains unchanged at 2GB and 6GHz effective, but are shrouded in the custom cooler Gigabyte designed which allowed [H]ard|OCP to push the memory to 6.46GHz once overclocked.  In the tests the card could compete with the slightly more expensive GTX680 which makes this card one of the fastest cards you can get.

"GALAXY’s new GeForce GTX 670 GC features a dual fan setup on a custom built PCB. GALAXY also tuned 670 GC with a strong 1006MHz overclock. We see how this compares to other video cards in its price range including a Radeon HD 7950 and GeForce GTX 580. Then we put the GALAXY GeForce GTX 670 head to head with a GeForce GTX 680."

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