Question Had this forever - "No Signal" - Monitor problems with DisplayPort ?

[Bassen]

Hey!

Ok so I've had this problem forever and I know how to recreate it a 100% so I also know how to avoid it, though it's annoying when I forget about it.
But perhaps there is a solution to the problem instead of just avoiding it so I'm giving it a shot because I haven't found anything else online other than advice to replace faulty PSU's which I've ruled out as being unlikely since I've used different PSU's with the same result over the years and there is no other problems with the PC.

Anyway here's the problem.

If I DON'T turn on the 2x BenQ monitors (DisplayPort) before or quickly enough after pushing the power button on the PC, then that will result in No Signal that can only be resolved by resetting/restarting the computer.
The SAMSUNG TV though, that runs on HDMI can be turned on without any problems and it never gets the No Signal error.
But trying to start any monitor connected with DisplayPort when the computer is already on the Windows login screen is impossible.
It always require me to reset/restart the PC or nothing will change.

Am I just out of luck when it comes to my older motherboard and it handles DisplayPorts poorly after POST/BIOS startup?
Or is this a normal "problem" and people just never turn their monitors off fully and just let them be on standby?


The specs:
Windows 10 Pro
MSI Z270 GAMING PRO CARBON ATX, Socket 1151, Intel Z270
16GB Corsair Vengeance PC21300/2666MHz CL16
Intel Core i7 7700K
GeForce GTX 1070 (this old GPU also had the same issue)
ASUS GeForce RTX 3070 Ti 8GB ROG STRIX GAMING OC (done multiple DDU's over the years on both the old + this new GPU and run with fresh driver installs most of the time)
And I've used 2 different PSU's over the years
Corsair AX 1200W 80+ Gold (The older PSU that was replaced a few years back)
Corsair RM850 850W 80+ Gold (The new PSU and still the no signal result can be created, so I guess you can rule out a faulty PSU?)

And on to the monitors/TV:
2x BenQ 27" 144Hz XL2720Z using 2x DisplayPort cables of the same brand (Accell B142C-010B DisplayPort to DP Latching Cable) have tested other cables too but the same result.
Have also tried windows own monitor drivers and different custom firmwares but I'm now running with ZOWIE XL LCD (DisplayPort) drivers for both monitors.
1x SAMSUNG UE55F6475SB using 1x Standard HDMI Cable, have tested other HDMI cables and still no change for the 2x DisplayPort monitors and all HDMI devices always work. The TV is running on Generic PnP Monitor drivers.

 

[geofelt]

Some thoughts:
Monitor drivers probably do nothing, I think they are mainly documentation.

If you forget and start up with one monitor working, right click on the desktop to get to display settings. There you will find a detect button that might find your displays.

Ultimately, you may find the solution in your bios settings as related to energy savings.
Try to disable the most aggressive of energy savings options.

Lastly, consider using sleep to ram(no hibernate) instead of power off.
That will put the pc and monitors into a very low power state that is very close to a full power off. The benefit is that sleep/wake becomes only a handful of seconds.

You may also want to try a HBR2 rated dp cable:

How to Choose a DisplayPort Cable and Not Get a Bad One - DisplayPort

www.displayport.org

 

[Bassen]

Some thoughts:
Monitor drivers probably do nothing, I think they are mainly documentation.

If you forget and start up with one monitor working, right click on the desktop to get to display settings. There you will find a detect button that might find your displays.

Ultimately, you may find the solution in your bios settings as related to energy savings.
Try to disable the most aggressive of energy savings options.

Lastly, consider using sleep to ram(no hibernate) instead of power off.
That will put the pc and monitors into a very low power state that is very close to a full power off. The benefit is that sleep/wake becomes only a handful of seconds.

You may also want to try a HBR2 rated dp cable:

How to Choose a DisplayPort Cable and Not Get a Bad One - DisplayPort

www.displayport.org

I didn't find any major energy savings options in the BIOS and all the non-essential options were disabled anyway.
The only options that is turned on under Power Management is the "Restore after AC Power Loss", everything else in there is disabled.

I do have to completely switch off my PC a lot during summers because of thunderstorms etc.
So I usually turn the PC and every other machine off and pulling the plugs completely during this.
Don't think the sleep to ram would work without the plug being connected to the electricity.

But as I said at the start of my post I'd like to find a solution to the problem instead of workarounds.

I might have to try with a HBR2 rated dp cable one day, I've already gone through different brands and a couple of these dp cables back in the days when I first made the switch from DVI to DP and using 2x 144 Hz monitors.

Thanks for the tips

 

[geofelt]

Of course, sleep to ram will not work for a disconnected pc.

Because you unplug the pc from the wall, the pc can no longer maintain knowledge of connected monitors.
I suspect that if left plugged in, things would work.
But, of course, that would keep you exposed to a power surge from the wall that could damage parts.
I know, I had that happen. Even when all was connected to a APC UPS.
It was recommended that I use a SURGEX surge protective device:
https://www.ametekesp.com/surgex
They are expensive. Most surge protectors are of the self destruct kind.
If a surge hits, they destruct.
SURGEX will reset.