Monitor Won't Stay In Standby

By dogknees ·
I've got a problem with my new PC. My monitor, which is not new but about 20 months old won't stay in Standby. When I shutdown the PC the monitor enters standby, but some time later (not sure how long as it happens overnight) the Monitor wakes up. When I get up in the morning, I'm greeted by a nice blue screen.

New PC is running win7 x64. All settings appear to be correct as the monitor does go to standby, but something triggers it later. The monitors settings have not changed and it was working correctly on the previous PC.

Any ideas?

This conversation is currently closed to new comments.

Thread display: Collapse - | Expand +

All Answers

Collapse -

"powercfg -lastwake"

by robo_dev In reply to Monitor Won't Stay In Sta ...
Collapse -

Reponse To Answer

by dogknees In reply to "powercfg -lastwake ...

The PC doesn't start, just the monitor. The PC stays shutdown until I hit the power button.

Collapse -

Am I reading this correctly?

by OH Smeg Moderator In reply to Monitor Won't Stay In Sta ...

When you shut down your PC the monitor fails to stay in Stand by Mode.

Are you trying to say that you turn off the computer but not the monitor?

Why would you even attempt this?

What happens is that a Power Spike overnight causes the Monitor to turn on and without any input from the computer which is turned off it sits there waiting for something to tell it what to do. The easy solution is to turn the Monitor off before going to bed.


Collapse -

Reponse To Answer

by dogknees In reply to Am I reading this correct ...

When I turn off my PC it puts the monitor into standby. This is the normal behaviour when you shutdown.

The issue is that at some time later the monitor (but not the PC) wakes up from standby. Normally this should occur when you start the PC.

If it's a power spike, then it didn't exist 2 weeks ago. The monitor has been in use and has worked correctly for over 2 years.

I agree that I should turn it off to save power, but when I don't I expect it to behave.


Collapse -

Well to check the system

by OH Smeg Moderator In reply to Monitor Won't Stay In Sta ...

You could always plug the monitor into a Filtering UPS and see if it continues to turn back on.

But with all things like this it is most defiantly a Power Spike which may not be in your residence but somewhere in your neighborhood. Things like Large Drain devices can cause this particularly when you are towards the end of a Mains Distribution Line or there is heavy Industry involved.

At one place I had the customers PC turn itself on overnight and that was traced to a new fridge that had been installed 2 doors down. Admittedly there they had poor Mains but these things happen. At another place a Reverse Cycle Air Conditioner would turn on a PC when it was set to cool but not heat some time over night after the owners went o bed.

I've also seen a case of a external Dial Up Modem being turned on which would start the computer running. Not overly common but it does happen. You need to look at the Power Draw on the Mains to see if something different is happening. Often something as simple as a Cold Snap can cause issues like this when there is Electrical Central Heating involved,

Personally I have never had to trace down a monitor turning itself on because all my clients turn them off when they leave even if they leave the PC running.


Collapse -

Reponse To Answer

by dogknees In reply to Well to check the system

If I attach the monitor to a different PC, it doesn't come out of standby. Same wall socket, same plugboard, same everything except the PC. How would a spike cause this behaviour?

>>At one place I had the customers PC turn itself on overnight ....

It is not the PC that starts up, it's just the monitor.

Collapse -

Try unplugging the monitor from the PC

by robo_dev In reply to Monitor Won't Stay In Sta ...

Normally what 'wakes up' the monitor is the presence of a video signal from the PC. So if the monitor wakes up without it's signal cable plugged in, then there could be a more serious issue.

If the PC is truly fast asleep, then either you're getting a juicy power surge through the sleeping PC or from the power mains, as Col alluded to, above, or perhaps the monitor and/or it's power supply is going bad.

Collapse -

Monitor On

by deadbob In reply to Monitor Won't Stay In Sta ...

Get a UPS and then you will have no power spike problems and do like the first gentleman suggested. Just turn the monitor off at night. Saves power and your monitor will last
longer also!!

Collapse -

cables, shields and ground-to-earth

by PhilippeV In reply to Monitor Won't Stay In Sta ...

First check the state of all cables and connectors (including those within the PC case), and their correct and complete insertion in their sockets/plugs, and the correct linking to ground and earth of all shields, including the shields of your video cable which should have a strong contact with the terminal connectors on both sides (some cables are incorrectly mounted and forget to connect these shields).

Beware also of silent blocks : they may isolate the screws that normally ensure the ground linking. And some screws may be painted with isolating material (like glue), or missing (so that not all grounds are fuly interconnected within the PC case).

Make sure that all internal devices are fixed with at least one screw on their grounded case (including PCI boards, disks and CD/DVD burners).

Any unused cable should not remain connected on one end: remove/disconnect those extra cables that are acting like amplified antennas, even if their gain is very small.

Unused cables should never exceed about 5 cm of length, otherwise it will capture a lot of long-range and highly penetrant VHF signals, with enough gain to generate an oscilation that will charge the circuits on your motherboards.

Also make sure that the monitor and PC have their A/C cable connected to earth (beware of cheap A/C outlet multipliers missing the ground-to-earth cable, if you live in an area with strong VHF emitters above the regulatory level of 57 dBm or 5V/m : this may happen if you're within about 50 meters from a strong GSM or FM radio antenna, or within 1 km of a TV emitter, or if you have incorrectly shielded neon lights, or within 300 meters of a high-power factory or railway station, or a high-voltage transformer in the street, which locally amplifies all the power spikes from the neighbourhood in the power grid).

Finally, make sure that you don't use any A/C wall sockets that were mounted in your home for high-power engines only protected by a 5 ampere fuse (such as oven, water heaters, wash machine...). For all your digital equipment, use only standard low power sockets (with 0.5A or 1.0A fuses).

Note that in rural areas, your electric supply may be delivered with 3 phases (this saves lots of energy within the long cables in your public power grid): in that case, your home installation normally distributes the power equally on each phase, and not all the wall sockets use the same phase. Normally, your home installaton includes a special "triangle-star" transformer to generate the point of ground that should be connected to earth, but some old installations are still missing this transformer. In that case, you don't have a solid ground-to-earth connection, and there's a constant oscillation between the phases, so that none of them are using the same ground. In that case, if your PC is connected to one wall socket, and your monitor to another one, they may have problems to stabilize their grounds which are constantly oscillating at 50/60Hz between each other, relative to the earth.

Only a qualified electrician will help diagnostic your old electric installation, and detect that you need the installation of the special transformer for connecting the low-power wall sockets and lights. (The electric heaters and high-power sockets won't use this transformer, but will be connected directly to the 3-phase supply, on separate sockets, via the 2-5 amperes fuses).

Don't mix multiple A/C wall sockets for digital devices that share any digital or analog signal connection via some cable (here the VGA or HDMI cable) ! Ideally the PC and monitor should share the same wall socket, but this could also be an audio cable to your Hifi system (and in frequent cases, the Hifi or flat TV will be on another wall socket : in that case, you may need to check that all sockets are effectively properly grounded to earth with the special transformer to avoid resonating oscillations between distinct phase-neutral pairs on your A/C outlets).

The special transformer above simplifies the connection because it will allow an interconnection of all neutral points of each phase-neutral pair in the triangular distribution, and this common neutral will also be grounded to earth in the transformer, before your home distribution to the various sockets of each phase. But beware also that the transformer may also be damaged with one circuit burnt (in that case the triangular mounting no longer equilibrates the power used across phases within the transformer, and grounding becomes unstable). This can create very powerful ERM levels everywhere in your home, which will be captured by every unshielded numeric cable (and you may see that your lights bulbs are burnt too often, or ou could see electric arcs each time you plug or unplug a cable on the sockets: call a qualified electrician to inspect the transformer, and note that your energy billing will rise very significantly if you don't repair it).

Collapse -

Monitor Won't Stay In Standby

by stuttgartt In reply to Monitor Won't Stay In Sta ...

I've had the same/similar problem(s) and it had nothing to do with power spikes. I leave my Win7 64 bit to go to sleep by itself as I usually have some task in progress at bedtime, defrag, scan, record etc.The monitor would go off but when I got up the dimmed screen would have frozen after waking sometime shortly after. The screen clock would be reading whatever time it woke up. (eg, Go to bed at midnight screen would say 1am) After trial and error discovered my new mi-fi (I think they call them) mobile broadband device was the culprit. I turn it off at night now and that problem has stopped. The blue screen problem I had turned out to be related to iTunes being affected by a useless little start-up program that Adobe slipped into one of their updates. Blue screen of death, unexpected shut down and my iTunes library would have vanished! (thankfully not the actual music files) That one took me weeks to fix. I never seem to have trouble with malware, just different programs not getting along with each other! You say the monitor is ok with another pc so maybe it's just something incompatible on the problem pc not that someone installed a fridge two doors down This may have nothing to do with your problem but may give you some ideas, hope it helps. 64 bit, it's the future of computers once they iron out all the bugs.

Related Discussions

Related Forums