GS usually stands for Golden Sample. By that, Gainward means a selection of cards that should be able to achieve the highest overclocks. But since Nvidia isn't allowing factory-tuned clock rates, this is a card that technically shouldn't exist.
Those restrictions weren't made clear to board vendors until after the cards and components were already manufactured, though. As a result, this product was allowed to find its way into our hands. Be that as it may, the BIOS still plays by Nvidia's rules.
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