gigabyte told me this is a RESERVED CODE , what does it mean ?
The thing is, that after the POST, the code doesn't mean anything! It's just some kind of wierd BIOS 'glitch' - and, if it's your only symptom - just ignore it... The codes are only valid during the POST (that's why they're called 'POST codes'!), and large numbers of them are either 'reserved' or 'undefined'; means that, either there is no such step in the initialization, or the step is optional to particular BIOS/hardware...
Here are the first few:
00 ... in BIOS menu
01 Force chipset defaults
03 Initial Superior_Early_Init switch
05 Blank out screen, Clear CMOS error flag 06Reserved/Unused
07 Clear 8042 interface, Initialize 8042 self-test
08 Test special keboard controller for Winbond 977 series superIO chips, enable keyboard interface
0A Detect PS/2 mouse/keyboard
0b Detect Onboard Audio
0E CMOS Integrity Check
...so you can see, seven of the first sixteen are listed as 'Reserved/Unused' - not at all uncommon.