When I try to start an Optiplex GX520 SFF, the 1, 3, and 4 indicator lights come on and the bios does not load, no beeps. Sometimes the hard drive light comes on also. Any thoughts?
Bad Power supply, Bad Motherboard, Bad Processor.
Your power button light and hard-drive light may indicate a computer problem.
Power is on, and the computer is operating normally. On the desktop computer, a solid green light indicates a network connection.
No corrective action is required.
The computer is in a power-saving mode (Microsoft® Windows® XP).
Press the power button, move the mouse, or press a key on the keyboard to wake the computer.
Blinks green several times and then turns off
A configuration error exists.
Check the diagnostic lights to see if the specific problem is identified.
The Dell Diagnostics is running a test, or a device on the system board may be faulty or incorrectly installed.
If the Dell Diagnostics is running, allow the testing to complete.
If the computer does not boot, contact Dell for technical assistance.
A power supply or system board failure has occurred.
See "Power Problems."
Solid green and a beep code during POST
A problem was detected while the BIOS was executing.
See "Beep Codes" for instructions on diagnosing the beep code. Also, check the diagnostic lights to see if the specific problem is identified.
Solid green power light and no beep code and no video during POST
The monitor or the graphics card may be faulty or incorrectly installed.
Check the diagnostic lights to see if the specific problem is identified. See "Video and Monitor Problems."
Solid green power light and no beep code but the computer locks up during POST
An integrated system board device may be faulty.
Check the diagnostic lights to see if the specific problem is identified. If the problem is not identified, contact Dell for technical assistance.
To help you troubleshoot a problem, your computer has four lights labeled "1," "2," "3," and "4"on the front or back panel. The lights can be off or green. When the computer starts normally, the patterns or codes on the lights change as the boot process completes. When the computer starts normally, the patterns or codes on the lights change as the boot process completes. If the POST portion of system boot completes successfully, all four lights display solid green. If the computer malfunctions during the POST process, the pattern displayed on the LEDs may help identify where in the process the computer halted.
The computer is in a normal "off" condition, or a possible pre-BIOS failure has occurred.
The diagnostic lights are not lit after the computer successfully boots to the operating system.
Plug the computer into a working electrical outlet and press the power button.
A possible BIOS failure has occurred; the computer is in the recovery mode.
Run the BIOS Recovery utility, wait for recovery completion, and then restart the computer.
A possible processor failure has occurred.
Reinstall the processor and restart the computer.
Memory modules are detected, but a memory failure has occurred.
A possible graphics card failure has occurred.
A possible floppy or hard drive failure has occurred.
Reseat all power and data cables and restart the computer.
A possible USB failure has occurred.
Reinstall all USB devices, check cable connections, and then restart the computer.
No memory modules are detected.
Memory modules are detected, but a memory configuration or compatibility error exists.
A failure has occurred.
This pattern also displays when you enter system setup and may not indicate a problem.
After POST is complete, all four diagnostic lights turn green briefly before turning off to indicate normal operating condition.
Your computer might emit a series of beeps during start-up if the monitor cannot display errors or problems. This series of beeps, called a beep code, identifies a problem. One possible beep code (code 1-3-1) consists of one beep, a burst of three beeps, and then one beep. This beep code tells you that the computer encountered a memory problem.
If your computer beeps during start-up:
Microprocessor register failure
NVRAM read/write failure
ROM BIOS checksum failure
Programmable interval timer failure
DMA initialization failure
DMA page register read/write failure
Video Memory test failure
1-3-1 through 2-4-4
Memory not being properly identified or used
Slave DMA register failure
Master DMA register failure
Master interrupt mask register failure
Slave interrupt mask register failure
Interrupt vector loading failure
Keyboard Controller test failure
NVRAM power loss
Invalid NVRAM configuration
Screen initialization failure
Screen retrace failure
Search for video ROM failure
No timer tick
Gate A20 failure
Unexpected interrupt in protected mode
Memory failure above address 0FFFFh
Timer-chip counter 2 failure
Time-of-day clock stopped
Serial or parallel port test failure
Failure to decompress code to shadowed memory
Math-coprocessor test failure
Cache test failure
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