Number of beeps
One short beep
Two short beeps
Three short beeps.
One long and one
One long and two
Two long and two
Many of these following codes indicate a more serious fault and the
BIOS stops. Switch off for 20-30 seconds and try again. If the fault
persists, make a note of it and call your maintenance provider.
Number of beeps
If no beeps are heard at all the speaker may be
disconnected or there may be a speaker circuitry
Marks the completion of POST and no
functional errors found. You will also get a single
beep if you press an invalid key for a power-on
Indicates and draws your attention to an error
during POST. This should be accompanied by
an error message.
System memory error, normally accompanied by
BIOS error code 201. Beeps are used when the
video cannot display the code.
Could indicate a serious failure of the system
motherboard, or a failure of the speaker circuitry.
Usually indicative of a keyboard key stuck down,
but may be due to the keyboard interface failing.
POST has detected an error on the video adapter
in the system. There may be no display on the
This means that either the video system is faulty,
or that a video I/O adapter ROM is not readable.
The video subsystem cannot be supported by the
main system POST. This can occur when the
video subsystem is replaced or changed on site.
CMOS write/read test failure
BIOS ROM checksum failure
Programmable Interval Timer test failure
DMA initialisation failure
DMA page register read/write test failure
RAM refresh verification failure
First 64K RAM test failure
First 64K RAM parity test failure
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