BIOS related problem with the card. For example, I have a Sapphire card that was unstable at factory overclocks, RMA'd it twice and it is still unstable. The warranty expired so I flashed the card to a newer, HD 5870 spec clocks and the card has been stable since. No. I would only flash when the card is outside of warranty and by then, there should only be a handful of BIOS that are suitable and stable for the card. If the card is stable, there's no reason to update it.