1 long beep A memory problem: remove and reseat memory.
1 long, 2 short or 1 long, 3 short Video card problem or problem with its memory.Replace the graphics card or its memory.
Continuous A memory and/or video problems. Reseat or replace
memory and/or graphics card.
1,1,3 CMOS unreadable. Replace the motherboard.
1,1,4 BIOS failure. Replace the BIOS.
1,2,1 The timer chip has failed. Replace the motherboard.
1,2,2 or 1,2,3 or 1,3,1 or 1,3,3 or 1,3,4 or 1,4,1 or 4,2,1 or 4,3,1 or 4,3,2 or 4,3,3 Motherboard error; replace it.
1,3,3 Memory problems. Try reseating or replacing RAM.
1,4,2 Faulty memory. Test and replace your RAM.
2,any, any Any beeps after two indicates bad memory. Run a
memory checking utility and replace RAM as necessary.
3,1, any Your motherboard has a faulty chip; replace it.
3,2,4 Keyboard controller error. Replace the keyboard,
controller chip, or the motherboard to resolve it.
3,3,4 No video card. Try reseating it or replacing it.
4,2,2 or 4,2,3 Replace the keyboard. If this persists, it’s
a motherboard problem; replace it.
4,2,4 Remove and replace all PCI cards one by one to find
the faulty one, then replace it.
4,3,4 Clock error. Reset the motherboard clock using
its set-up program. Replace the CMOS battery if
necessary. If this fails, replace the power supply.
4,4,1 or 4,4,2 Use the motherboard manual to disable the serial
ports and add an I/O card to replace them.
4,4,3 Maths coprocessor malfunctioning. Use a low-level
diagnostic program to confirm this, then disable it.

None Faulty speaker, broken mobo or PSU problem.
1 short beep RAM refresh, interrupt timer or interrupt
controller failure. Replace your motherboard.
2 short beeps or 3 short beeps Indicates memory problems. Check the seating of
memory chips or replace the memory.
4 short beeps System timer failure. Replace the motherboard.
5 short beeps CPU failure.
6 short beeps Keyboard control chip error. Replace keyboard.
If it persists, chip may need to be replaced/reseated.
7 short beeps CPU exception error. Replace CPU and/or mobo.
8 short beeps Video card failure. Reseat the graphics card.
9 short beeps ROM checksum error. BIOS ROM is bad – replace it.
10 short beeps There’s a problem with the CMOS. Replace your mobo.
11 short beeps L2 cache memory failure. Replace L2 cache memory.
1 long, 3 short Memory test failure in RAM over the first 64k.
1 long, 8 short Display test error. Missing or broken video card.

Excerpt from PC.Answers August 2005