Some of the reasons why Hp does not boot are overheating and a faulty main board. Booting can also fail to take place when some components lift slightly off the PCB (Printed circuit board) and stop contact.
The following are the recommended solutions to HP Pavillion dv2500 booting problem:
First recommended solution
Unplug the computer power and then open up the case. Disconnect the cable of the card reader at the card reader itself. This disconnection is better than disconnecting the cable from the end that attaches to the motherboard header. Ensure that the cable end does not touch any components that are metallic to avoid electric faults such as short circuits. With the power cable being disconnected, boot the computer and leave it for about 10 minutes. Then shut down the computer and reconnect the cable to the card reader (HP Pavilion, 2012). Reboot the computer and the problem is solved. The card reader will work and the computer will not hang especially at POST.
This process solves the booting problem because when you fire up the computer with the cable disconnected, the card reader resets its firmware by grounding through the case like a CMOS (Complementary Metal-Oxide Semiconductor) Reset jumper on a mother board.
Second recommended solution
When the computer fails to boot, perform a hard rest as the first procedure as follows. Disconnect any device such as modems, USB jack pins that is connected to the machine. The importance of this step is to ensure that during testing; only the computer and not other devices is being tested.
Next, disconnect the power supply and remove the battery. Then, press the power button for about twenty seconds or slightly more. Reconnect the power supply again without connecting to the battery. Press the power button and then look for glowing LEDS (Light Emitting Diodes) near the caps lock key as well as the num lock key. Listen if there are any sounds of a disk drive and fan turning. This completes the hard reset procedure. Proceed and look if there are any specific error messages. Perform both EFI (Extensible Firmware Interface) and Non-EFI troubleshooting tasks and then remove non-system disk from your computer (Tom, 2012). Restore the BIOS (Basic Input/output System) default settings and follow this by performing both Memory test and Hard Drive Test respectively. Reinstall Windows operating system. Your computer should now be able to boot successfully.
Third recommended solution
Blow out or clean your computer inside of dust. Remove the memory modules, clean the contacts and reseat them. Take out the video card if it does have one and try on board. Remove any other cards such as modems, USB disks or TV tunner. Disconnect the twenty four PS plug from the main board try shirting GREEN with any BlACK by using a wire or a paper clip. The PSU (Power Supply Unit) should turn ON and this helps in knowing if the PSU is working (HP Pavilion, 2012). Now disconnect Front pannel connector on the main board and try to short the pins for the power button. This step is import since it helps in knowing if the power button is the cause of the fault.
References
Tom, H. (2012). 56096-2-dv2500-power. Retrieved on 19-Nov-2012 from www.tomshardware.com/forum/
HP Pavilion, (2012). Resolving Start Up and booting problems. Retrieved on 19- Nov-2012 from h10025.www1.hp.com/ewfrf/wc/document?docname=c07298426&tmp_task=setupCategory&cc=us&dlc=en&lc=en&product=3379103
