no monitor input signal, keyboard doesn't respond

[DW1234X]

My hp a6500f desktop powers on, with a "No input signal" on the monitor, then goes to sleep.  The unit is 1.5 years old.  No parts replaced.  Not bumped.  One day, for no apparent reason stopped working.  The key board lights up when 1st turned on, but then cannot get any lights for cap or num lock.  Mouse has light, green light on backside of cpu is green when plugged in.  All 3 fans are working.   I have unplugged everything, removed and re-inserted memory cards, checked for loose components internally and externally.  The monitor, cables and keyboard are good.  Tested on another computer.  Tried booting with recovery discs, but still no input signal to monitor.  Any suggestions?  This pc has a seagate 500mg hard drive which can go bad.  Never saw the fix posted on the hp website.

[TheOldMan]

It sounds like the video card or onboard video has gone out.  If it has a removable video card, try a different one.  If it has onboard video, try a replacement video card.  According to the product information, it has an open PCI-eX16 for a video card and uses onboard video, if it has not been changed from the factory setup.  A simple and inexpensive video card can be used to replace the onboard video for testing or for just left installed if it works OK after the test.  If it will not show any on screen video with the recovery discs, then that is the only solution (you stated the monitor was tested elsewhere and is working) other than a bad power supply.  Power supply failure can happen like stated also.  Of course, a competent computer shop would be another choice.

[DW1234X]

I put in a new video card, powered on and nothing changed.  Since there is no input to the monitor, I cannot access the bios.  Are you saying to put in the new card (the old one is part of an integrated board) and re-boot with the recovery disc?  Are there other steps to replacing.  The HP website does not help with this scenario.

[TheOldMan]

If it was the video (onboard in you case) make sure the monitor is connected to the new video card.  It should at least show the BIOS slash screen if it is going to work. If that is not happening, I suppose the power supply is next on the list.  If you can find a power supply testor someplace, that is also an option before replacing the PS.  I would have to assume the Recovery Disks did not do anything if nothing else came on.