my brother has a HP pavilion 8756c. It came with 128ram. About 6 months a go i added another stick of 128 for him so he would have 256. It worked fine until now. It says he only has 255 when you check it in his properties. But his bios still says 256. I have switched the ram around still nothing. I put my ram which is still PC100, but 512 and it read 511. He would not care but if a game requires 256 he cant play it says he doesn't have enough ram. It is only reading 255 of it. Or 127 if i take one out. What has happened to his PC. I have already deleted windows, reinstalled it. And I have checked to see if there is a bios update for his machine , but there is not. Well according to hp. PLEASE HELP.