Beep code on Mainboard

When a serious error occurs, the computer does not show message but emit a series of long and short beeps instead. Beep is the way you tell the computer what if there is a serious error occurs. These codes depend on the BIOS of your PC. There is no official standard for this beep code on mainboard because many brands of BIOS out there.

Beeps	Descriptions
1	The memory refresh circuitry has failed
2	Parity errors have been detected in the first 64 KB of memory
3	A failure has occurred within the first 64 KB or memory
4	System Timer failure: Timer 1 on the mainboard does not work properly
5	The CPU has generated an undetectable error
6	8042 Gate-A20 failure: BIOS cannot switch the CPU into protected mode
7	The CPU has generated an exception error
8	The video adapter is missing, or the memory on the adapter has generated a failure
9	The ROM checksum value does not match the value in BIOS
10	The shutdown register for CMOS interrupt channel 2 has failed POST; the system board cannot retrieve CMOS contents during POST
11	Level-2 cache memory has failed the tests, and has been disabled
2 short	POST has failed, caused by a failure of one of the hardware tests
1 long, 2 short	Failure in video system: a checksum error was encountered in video BIOS ROM, or a horizontal retrace failure has been encountered
1 long, 3 short	Failure in video system: the video DAC, the monitor detection procedure or the video RAM has failed
1 long	POST procedures have passed