I think I've only seen Radeon HD58xx (Cypress) cards with either 1GB or 2GB. Does anyone know what the maximum addressable memory is with Cypress? Could an OEM have made a 3GB, 4GB, or 8GB card?
Since you haven't received any replies yet on the forums, try contacting AMD support either by email (http://emailcustomercare.amd.com/) or by phone (http://support.amd.com/us/contacts/Pages/global-technical-support.aspx).
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