I have a 256GB gigastone card and its capacity is that of a typical vendor, defined in decimals, 256 billion bytes: 256,020,316,160 bytes (238GB). This "512GB" version came with a "500GB" capacity: 500,259,749,888 bytes (465GB). It doesn't seem like much, but why can't they just be honest with the description and sell it as a 500GB card? I have a feeling they are taking advantage of naive users who gloss over large numbers and assume it's a normal difference between decimal and binary conversion.
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