Preparation

• To prepare the Compaq Presario 900 for troubleshooting, remove the battery and all CD/DVD discs and media cards. Disconnect all peripherals including USB devices and printers. Plug the power cord into an active wall socket. Press the power button to switch on the computer.
  
  

Black Screen Error ("Black Screen of Death")

• If the BIOS encounters problems querying hardware components and loading devices into memory, the system displays a black-screen error. Make sure the memory modules (located on the underside of the case) are firmly seated. Press F2 at startup to perform the Memory Self Test (labeled "Start-Up Test "or "Memory Test") and the Hard Drive Test (labeled "Hard Disk Test" or "Primary Hard Disk Self Test"). If this does not identify the issue, reset the BIOS to default settings. To reset the BIOS, press F10 at startup to access the BIOS setup and press F9 to load the default BIOS settings. If necessary, repair the Master Boot Record (Windows XP only) using the Windows Operating System Disc. If none of these steps resolves the problem, reset the computer to its original settings by pressing F11 repeatedly at startup to enable Compaq Presario PC Recovery.
  
  

Blue Screen Error ("Blue Screen of Death")

• If the BIOS encounters hardware failures or problems loading the operating system, the system displays a blue-screen error. Press F2 at startup to perform the Memory Self Test and Hard Drive Test. If this does not identify the issue, press F10 at startup to reset the BIOS to default settings. If the error persists, press F8 at startup to restore the system to the Last Known Good Configuration, or boot into Safe Mode and run Microsoft System Restore. If necessary, boot into Safe Mode and visit HP.com to download the current BIOS and device drivers. Use Windows Update to install current Windows files. Uninstall recently installed software programs ("Control Panel"; "Add or Remove Programs"). If none of these steps resolves the problem, reset the computer to its original settings by pressing F11 repeatedly at startup to enable Compaq Presario PC Recovery.
  
  

Windows Logo Screen Error

• If the Windows operating system encounters problems because of a hardware failure, device driver conflicts or software issues, the system freezes at the Windows logo screen. Press F2 at startup to perform the Memory Self Test and Hard Drive Test. If this does not identify the issue, press F10 at startup to reset the BIOS to default settings. Restore the default VGA Low-Resolution graphics settings by pressing F8 at startup, download and install the newest graphics drivers, then select the desired resolution. Uninstall recently installed software programs. If the error persists, press F8 at startup to restore the system to the Last Known Good Configuration or boot into Safe Mode and run Microsoft System Restore. If none of these steps resolves the problem, reset the computer to its original settings by pressing F11 repeatedly at startup to enable Compaq Presario PC Recovery.