Startup BIOS communicates POST errors as a series of beeps
before it tests video.Search the web site of the motherboard or
BIOS manufacturer to know how to interpred a series of beep
codes.
With a mac what does two beeps followed by a pause then three beeps mean at start up but wont start?
Beeps at start up indicate that something is wrong. Often it is
a bad memory module, possibly not pushed in tight enough to form a
solid connection. (See links below)