The BIOS will produce audible beeps during the power-on self test (POST). These are low level hardware errors which generally result in your PC locking up hard right after the beeps. Usually requires a hardware fix.

American Megatrends, Inc. (AMI) error messages associated with the AMI BIOS beep codes are as follows:

 
Number    Error
of Beeps  Message   Action
--------  -------   ---------------
 
 1   DRAM refresh failure         Reseat memory or swapout with known good chips
 2   Parity circuit failure       Reseat memory or swapout with known good chips
 3   Base 64K RAM failure         Reseat memory or swapout with known good chips
 4   System timer failure         Replace motherboard
 5   Processor failure            Replace motherboard
 6   Keyboard controller          Reseat keyboard controller chip, replace keyboard  
       gate A20 error                controller chip, check for a keyboard fuse
 7   Processor virtual mode       Replace motherboard
       exception 
 8   Display memory R/W failure   Replace video card or video card memory
 9   ROM-BIOS checksum failure    Replace ROM chips or motherboard
10   CMOS shutdown register       Replace motherboard
       read/write error 
11   Cache memory bad             Replace cache memory 

Award BIOS only hase a single beep code: a single long beep followed by two short beeps. Any other beeps are probably a RAM (Random Access Memory) problems.

PhoenixBIOS beep codes are more complex. See Phoenix BIOS POST and Beep codes pdf.

Also see Power On Self Test Beep Codes for AMI and Phoenix BIOS

Dell purchased motherboards from various manufacturers. You will need to go to the Dell site to get the codes for the specific model you won. Dell support

Related:

Troubleshooting BIOS Beep Codes

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