Computer Screen does not wake up after long idle time

[squaref]

Hello,

I have seen several threads on this topic but none that addressed my problem. My issue is that in some instances the computer wakes up but there is no video signal. I use the desktop as a video server and therefore leave it on all the time.

Symptoms
- After leaving the desktop unused for a long time, the monitor will not wake up when switched on
- When the monitor does not wake up, if I try to force the desktop to switch off by pressing the on/off switch for 5 seconds, the desktop does not turn off - it actually re-starts immediately and the monitor is still not getting a signal (I am unable to turn the desktop off)
- The only solution in that case is to a) Switch off the PSU, b) Press the desktop on/off button for 30 seconds, c) Switch on the PSU, d) Press the desktop on/off button on again. After doing this, I get a monitor signal every time.
- If the computer just wakes up from a short sleep, then the monitor wakes up
- When the monitor is on, I can reboot the desktop and still get a monitor signal

What I did already:
- Changed the PSU
- Changed the CMOS Battery
- Changed the DVI cable between the computer and the monitor (this helped because prior to that, the monitor would not go on when the computer would wake up from sleep mode)
- Verified that the desktop and mouse can wake up the desktop
- I did not try with another monitor but when the issue happens, the monitor indicates that it does not receive a DVI signal

SPECS
HP Pavilion H8-1300Z with 6GB of RAM
AMD FX-6120 Six-Core Processor
AMD Radeon HD 7450
Windows 10 Home Edition 64-bit

Any idea would be most welcome!

 

[squaref]

UPDATE: I tested with another monitor and got the same problem. The 2nd monitor also does not receive a signal from the desktop

 

[kenghtt]

Hello Squaref,

Have you tried playing around with the sleep settings on both your Desktop and Monitor? When the monitor sleeps, does your desktop also sleep (do you hear your desktop running)?

 

[squaref]

Hello Kenghtt,

Thanks for the response.

The monitor goes to sleep mode independently from the desktop (because it is set to go to sleep mode after 5 minutes). When I put the desktop to sleep mode, the monitor goes to sleep as well. I can wake up the monitor and desktop from sleep mode and it works. The issue seems to happen after prolonged wake time.

Another update: I tried installing another Video card and my problem was still there. At this stage, it looks like the motherboard could be the issue.

 

[kenghtt]

Hello squaref,

I would highly suggest removing the sleep mode for both the desktop and monitor and keep them both on for a period of time. That way you can know if its the sleep issue. If either one decides to sleep when you had already turned it off, something more severe can be the issue, but if it does not go to sleep after a period of time, then it can be an issue relating to the sleep settings.

Please try the above, and then if possible, try reinstalling the operating system and see if that helps. As the information you provided, i don't believe it is a hardware issue....yet...

 

[squaref]

Hello Kenghtt,
Thank you. I will try the following (in sequence)
1) Remove the desktop sleep mode but allow the hard disk and monitor to go to sleep
2) Remove the desktop and hard disk sleep mode but allow the monitor to go to sleep
3) Remove all sleep modes
I will report back

 

[squaref]

Hello Kenghtt,
I did #1 above and it worked! The desktop has been 4 days with no issue - longest time ever. My Windows 10 installation is recent (from a Windows 10 disk - not OEM). Do you have suggestions as to how I can fix that sleep mode?

 

[kenghtt]

Hello Squaref,

I wonder if it is a hard disk issue. Though, if you happen to have another computer/laptop laying around, definitely test out your monitor just to make sure that the monitor doesn't wake up after a certain amount of time.

 

[squaref]

I actually tried another monitor with the same issue. Also, the hard disk is fairly new (I changed it when I installed Windows 10). One other element = when I had no video signal, I tried shutting down the desktop by pressing the on/off button for a few seconds. Typically this would turn off the desktop but in my case, the desktop would turn right back on.

 

[squaref]

I am closing this thread as preventing the desktop from going to Sleep did fix my issue. I am still unsure why it does that, as I have a recent Windows 10 installation. Thank you Kenghtt for your help!