According to your manual, error code 99 is a problem related to PCI-E devices (i.e., graphics card). Please re-install PCI-E devices or try installing them in other slots. If the problem still exists, please remove all PCI-E devices or try using another VGA card.
Error code 64 is a chipset initialization error. It says to clear CMOS to fix this. See page 36 of your motherboard manual for how to clear cmos using jumpers.
So try reseating your graphics card. If that doesn't fix the problem, try resetting cmos.
Your motherboard manual is here: ftp://126.96.36.199/manual/990FX%20Extreme9.pdf