I`ve got a Dell OptiPlex 745 desktop system which will often fail to boot after a restart. The diagnostic lights show a 1-2-3 pattern which has no definitive solution in the manual. Pressing the power button shuts down the system immediately after this particular boot failure. Pressing the power button from an power off condition always results in a successful boot. This problem only occurs after a Windows restart and then not with every restart but intermittently.I`ve changed the ram even reinstall windows and replaced the sata cables and I still get the same problem
Changing Ram with other Bad Ram is not going to fix the problem.
There are 4 lights .
Hard Drives go bad.
Ram must be matched vendor and in pairs but can be tested as a single stick at a time.
Long term memory diagnostic and or Live Linux Boot DVD would be in order.
A failure has occurred.
This pattern also displays when you enter system setup (see Entering System Setup) and may not indicate a problem.
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 (see Diagnostic Lights).
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 (see Contacting Dell). <ADMIN NOTE: Broken link has been removed from this post by Dell>
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 (see Diagnostic Lights).
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.
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 (see Diagnostic Lights). If the problem is not identified, contact Dell for technical assistance (see Contacting Dell). <ADMIN NOTE: Broken link has been removed from this post by Dell>
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.
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.
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
Fill out the Diagnostics Checklist as you complete these checks.
If the message is not listed, see the documentation for the operating system or the program that was running when the message appeared.
A filename cannot contain any of the following characters: \ / : * ? " < > | — Do not use these characters in filenames.
A required .DLL file was not found — The program that you are trying to open is missing an essential file. To remove and then reinstall the program:
Alert! Previous attempts at booting this system have failed at checkpoint [nnnn]. For help in resolving this problem, please note this checkpoint and contact Dell Technical Support — Contact Dell (see Contacting Dell) <ADMIN NOTE: Broken link has been removed from this post by Dell> and report the checkpoint code (nnnn) to the support technician.
Alert! Air temperature sensor not detected — For any computer type except the ultra small form-factor computer, ensure that all cables are securely fastened to the I/O panel and to the system board and reboot your computer. If this does not resolve the problem or if you have an ultra small form-factor computer, contact Dell (see Contacting Dell). <ADMIN NOTE: Broken link has been removed from this post by Dell>
Attachment failed to respond — See Drive Problems.
Bad command or file name — Ensure that you spelled the command correctly, put spaces in the proper place, and used the correct pathname.
Bad error-correction code (ECC) on disk read — See Drive Problems.
Controller has failed — See Drive Problems.
Data error — See Drive Problems.
Decreasing available memory —
See Lockups and Software Problems.
Diskette drive 0 seek failure — See Drive Problems.
Diskette read failure —
See Drive Problems.
Diskette subsystem reset failed — Run the Dell Diagnostics (see Dell Diagnostics).
Diskette write protected — Slide the write-protect notch on the floppy disk to the open position.
Drive not ready — Put a floppy disk in the drive.
Gate A20 failure —
Hard-disk configuration error —
Hard-disk controller failure —
Hard-disk drive failure —
Hard-disk drive failure —
Insert bootable media — Insert a bootable floppy disk or CD.
Invalid configuration information - please run SETUP program — Enter system setup and correct the computer configuration information (see Entering System Setup).
Keyboard failure — See Keyboard Problems.
Memory address line failure at address, read value expecting value — See Lockups and Software Problems.
Memory allocation error —
Memory data line failure at address, read value expecting value —
Memory double word logic failure at address, read value expecting value —
Memory odd/even logic failure at address, read value expecting value —
Memory write/read failure at address, read value expecting value —
Memory size in CMOS invalid —
See Lockups and Software Problems.
No boot device available —
No boot sector on hard-disk drive — Enter system setup and ensure that the computer configuration information for the hard drive is correct (see Entering System Setup).
No timer tick interrupt — Run the Dell Diagnostics (see Dell Diagnostics).
Non-system disk or disk error — Replace the floppy disk with one that has a bootable operating system or remove the floppy disk from drive A and restart the computer.
Not a boot diskette — Insert a bootable floppy disk and restart your computer.
Not enough memory or resources. Close some programs and try again — Close all windows and open the program that you want to use. In some cases, you might have to restart your computer to restore computer resources. If so, run the program that you want to use first.
Operating system not found — Contact Dell (see Contacting Dell). <ADMIN NOTE: Broken link has been removed from this post by Dell>
Plug and Play Configuration Error —
Read fault —
Requested sector not found —
Reset failed —
Sector not found —
Seek error — See Drive Problems.
Shutdown failure — Run the Dell Diagnostics (see Dell Diagnostics).
Time-of-day clock stopped —
Time-of-day not set-please run the System Setup program —
Timer chip counter 2 failed — Run the Dell Diagnostics (see Dell Diagnostics).
Unexpected interrupt in protected mode — Run the Dell Diagnostics (see Dell Diagnostics).
WARNING: Dell's Disk Monitoring System has detected that drive [0/1] on the [primary/secondary] EIDE controller is operating outside of normal specifications. It is advisable to immediately back up your data and replace your hard drive by calling your support desk or Dell —
If no replacement drive is immediately available and the drive is not the only bootable drive, enter system setup (see Entering System Setup) and change the appropriate drive setting to None. Then remove the drive from the computer.
Write fault —
Write fault on selected drive —
<drive letter>:\ is not accessible. The device is not ready — The selected drive cannot read its medium. Depending on its medium type, insert a floppy, CD, or Zip disk into the drive and try again.
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