512mb OR 1gb. I guess it's not a misprint.
IMO That means "512MB Per GPU or 1GB total". Also, looking at sapphire's site, there isn't any mention of there being 2 different 3870X2s, also, the difference in the amount of RAM wouldn't ever equate to a £100 difference, especially as it's GDDR3. I honestly can't see any company making a 3870X2 with a total of 512MB RAM. Plus the fact that it refers to a 3870 Toxic card, check the manu-ref it points to a sapphire 3870 Toxic, £150 for one of them seems about the right price.

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