Due to a bug in the diagnostic software that validates the Radeon HD 2400 and 2600 cards, about 30,000 defective cards slipped through and was shipped out to stores. Vendors have been recalling the cards and it seems that not too many of the defective cards that have been sold. If you do have a defective card it can easily be fixed through a BIOS update, or more precisely reapplying the BIOS. The defect is not isolated to any specific manufacturer but spread across all vendors. The defective cards have been called back though, and will be fixed and replaced.
