AMD admits HD4830 BIOS mistake Page: 1
Some 4830's shipped with wrong BIOS
 
BIOS error on limited amount of HD4830'sAMD have issued a statement to Bit-Tech.Net, which details an error in which a limited number of HD4830 GPU's have been shipped with a pre-production version of their BIOS. This news comes only a week after the release of these cards. The pre production BIOS enables only 540 of the 640 stream processors and significantly affected performance.
 
AMD were quoted to have said the following regarding the issue:
 
"AMD has identified that, in addition to reference samples of the ATI Radeon™ HD 4830 boards sent to media with a pre-production BIOS potentially impacting the card’s performance, a very limited number of ATI Radeon™ HD 4830 boards were released to market with the same pre-production BIOS. This is in no way hardware related, and an updated BIOS fully resolves the performance limitation. Through consultations with AMD board partners, it has been determined with a high degree of certainty that fewer than 400 ATI Radeon™ HD 4830 boards from one AMD board partner, HIS, have reached the market with the pre-production BIOS incorrectly provided by AMD. As only a small number of HIS-branded ATI Radeon™ HD 4830 cards are impacted, we ask any customers that purchased an HIS-branded ATI Radeon™ HD 4830 to test the board using the GPU-Z utility (available at http://www.techpowerup.com/gpuz). If the GPU-Z utility reports fewer than 640 shaders, please visit the HIS website for information on how to update the card BIOS via a downloadable install utility."
 
Anyone who suspects they may have an affected GPU should follow the advice given by AMD, and it can easily be rectified with a BIOS update.
 
You can discuss in our forums here.