desktop is not sending signal to monitor

[paulri]

The last few weeks, this desktop that I'm working with has been acting up--after rebooting or a cold start, the computer will turn on (I can see the light behind the power button), and I can hear the hdd spinning, but there is no signal to the monitor. The monitor then announces that it sees no signal, and goes into sleep mode. 

I read online that one solution is to reset or adjust in some way, the CMOS battery. I have no idea what this process is. Do I just replace it? Or what? 

Is there any other solution that might fix this? there were no major updates to any software or hardware that I can think of.

[Grzwacz]

Hello paulri

If you shut the PC down and disconnect from AC power, and then depress power on switch to drain residual MB power, you can now open tower and remove the CR2032 watch battery. Then let the PC sit for about 10 to 15 minutes. Reinstall the battery or replace the battery and see if that helps. You are resetting CMOS to factory defaults when you do this..

Have you tried the monitor on a different PC (or different monitor on this PC) or tried using a different signal cable or port (DVI instead of VGA)?

Your PC factory operating system was Win 8.1. When did you upgrade to Windows 10? Windows 10 sometimes provides faulty graphics drivers that can cause this.

Question, do you now ever have video or is the PC DOA? No video leaves no way to see what is going on and makes troubleshooting impossible.

The obvious cause points to the graphics card or graphics card driver but this is not always true.

Are you using onboard Intel graphics or do you have an AMD or Nvidia graphics card installed?

If Intel, then try an inexpensive AMD or Nvidia card in PCIe x16 slot on the MB. If you have a graphics card installed, then remove it and try Intel graphics.

Other possible causes which require testing and swapping components are:

1. Power supply

2. RAM

3. Motherboard

Grzy

[paulri]

OK, I'll first update graphics drivers.

Since I'm opening up the tower anyways (if the driver update isn't available or doesn't work), would simply replacing the CMOS battery be a better option than taking it out, and putting the same one back in? It hardly seems like more work---or is there a good chance that taking it out, then putting it back in would resolve it?   I can easily get one  a few miles away, so if I have to replace it, its not a problem---its just that I'd rather not waste time if putting the old one back in won't do it.

[paulri]

There is video, after several successive shut downs and attempts to restart. 

I did use the method given above in the OP, so yes I can continue to troubleshoot. 

[Grzwacz]

Hello

Replace it, the battery is not expensive. A dying MB battery may not be the problem. It will not hurt to replace it.

Do you have video at some point? You can't do anything without video.

There are Windows 10 drivers by HP for Intel, Nvidia, or AMD for your PC here. You can't install the correct driver without video.

What graphics hardware are you using in this PC? Try different graphics hardware per my previous response.

Remove the RAM and boot. See if you get a missing RAM POST error message. Then try each stick of RAM in each slot to see if the PC will POST with display.

Try a different power supply if you have a spare one. The PS may have enough juice to power on the system but not power all components connected. Disconnect HDD's, optical drives, and others unneeded devices. 

Solving this type of error is tedious and can get expensive. It may be best to have a good tech check the PC. The tech has known good replacement components and can swap them until the bad component is found.

Grzy

[paulri]

Just checked. So far, since doing that bit with the power button, this computer has been fine---the monitor has been getting the signal. I tested it again today, and after powering down then cold booting up, the computer sent a signal to the monitor just fine. 

EDIT:  I guess I didn't explain earlier, but I unplugged the power cable, then pressed the power button on this computer for 30 seconds, then plugged it back  in, and powered it up. Since doing that, no problems have been detected, including today when I went over and shut it down, and powered it back up, myself. So perhaps that was it. 

OK if I do anything with the CMOS battery, I'll just replace it. They are cheap enough.

[paulri]

Some new info:

I was able to hook the monitor up to a laptop, and it worked fine---as soon as it was plugged in to the laptop, I got a nice image.

The pull the power chord out from the back, and press the power button for 30 seconds method, failed me today twice, so I'm not sure about that as a solution.

I used the HP link you gave me for drivers, and updated the two that had anything to do with video and graphics. I'll see if it makes any difference in the future.

Finally, I used Windows 10 check disk utility, and it said teh hdd itself was fine. I downloaded and ran the Crystal Disk Info, and it gave a Good rating to this hdd, and didn't uncover any problems. I have been wondering if the issue is a failing hard drive.

Instead of taking out the RAM disks, and then rebooting (because it takes several shut downs before the image from the computer finally is shown on the monitor)---would Windows' ram test be just as good? I remember doing this when trying to figure out if RAM was bad, in teh past.   That way, I would only have to reboot once to get into the test, and once to get out of it (instead of rebooting every time I was to swap out RAM or move the sticks around).

[paulri]

I just swapped out the CMOS battery, but it still isn't sending a signal to the monitor.

I have not yet toyed around with removing the sticks of RAM.