Question GPU or Monitor? Sleep mode issue

[roger911]

Issues with the monitor after it being unplugged for a certain amount of time, or after sleeping for extended periods (30 minutes or more). I've gone through my own troubleshooting steps and with Acer tech support. Ends up with an RMA filed for the monitor. About to ship the monitor in to Acer for the 3rd time, and would like to cross T's and dot I's so this issue can finally be put to rest. If the issue is GPU related, I don't want to waste Acers time or money. Any and all tips/advice/troubleshooting appreciated. I'm pretty convinced the issue is the monitor, but considering it was RMA'd twice... I've been wrong before.

Symptoms -

• Black screen, Orange LED indicator (Power available, but no signal)
• After waking computer up, no change.
• Cycling monitor power, no logo. LED turns off on power off and does not come back on.

Temporary fix -

• Unplugging power connector from monitor for 5 seconds and plugging back in. Logo pops up and screen re-connects.
• Unplugging DisplayPort connector from monitor for 5 seconds and reconnecting. Same as above.

Additional information -

• Secondary monitor that uses HDMI does not have this issue.
• Monitor has been RMA'd twice... and repair reports indicate the monitor works fine. (NOTE: Monitor comes back with source set to HDMI).
• PC system historically had issues with power supply, including minor cosmetic burn marks o

n the power port on the GPU (The PS port, and the GPU power cable however got melted). Power supply was RMA'd and everything worked fine.

• Same setup did not have this issue previously, it began occurring without any major software or hardware changes.
• Temperatures of the Computer system are stable and low (no higher than 50C at load, system is water cooled with an EK setup, GPU included in loop).
• Problem can seem intermittent. Sometimes monitor goes to sleep over night and wakes up in morning just fine, though usually anything longer than 30 minutes will cause the symptoms to occur
• Monitor had the same issue right after reception of an RMA
• Repair work history of monitor indicates screen replacement, fan replacement, power cable/supply replacement, and stand replacement.
• GPU stress tests fine, no artifacts, no instability.
• System is not overclocked in any way

System information (Desktop) -

O/S: Windows 11 Pro, latest update
Drivers: All up to date
CPU: AMD Ryzen 9 5950X 16-Core Processor 4.00 GHz
RAM: 32.0 GB DDR4
MOBO: TUF GHaming x570-pro (wi-fi)
GPU: TUF Gaming Geforce RTX 3090
Cooling: EK liquid cooling, 2x 360mm radiators, Waterblock on CPU and GPU, GPU has additional back plate cooling block
PSU: Asus 1200W Gold
Monitor: Acer Predator x27

Apps in commonly in background - Nvidia Experience, Steam, OneDrive, EpicGames

Edit: DisplayPort Cable was changed, problem persisted, Power Bar was replaced, problem persisted.

 

[JohnBonhamsGhost]

System information

you don't seem to list this power supply that has already malfunctioned once..

power cable/supply replacement

using 3rd party cables can also be a problem for many users.
you don't mention this make/model either.

 

[roger911]

you don't seem to list this power supply that has already malfunctioned once..

using 3rd party cables can also be a problem for many users.
you don't mention this make/model either.

Power supply is an Asus TUF 1200W Gold. It was not repaired but fully replaced by Asus, as the one that malfunctioned was hazardous. They took it and disposed of it.

The replaced power supply for the monitor (because the power cable is essentially a power adapter like a laptop charger), was replaced by Acer themselves so it's their own specific brand designed for use with the monitor.

The DP cable was what came with the monitor (Or video card... I don't know if the monitor came with one. If it did, that's the one, if not it came with the 3090), and has also been replaced with one from Canada Computers, and still has the same issue. (They both work, but I bought a new cable to rule out the cable being an issue)

 

[JohnBonhamsGhost]

Asus TUF 1200W Gold

have never seen a gold model, usually the TUF series is rated bronze.
and through the years they've usually been considered a mid-tier power supply.
with only a 6 year warranty i would not recommend for any use.
the fact that it already malfunction once and burned out a PCIe cable just lends to the idea that it is a lower quality model in general.

whether it's an issue with the monitor not "sleeping" properly
(it may just be an issue with this series in general, not your particular product)
(it's also possible that upon testing the lab found no such issue and just sent you the same monitor back),
an issue with your OS being corrupted,
an issue with your power supply,
or an issue with a damaged graphics card due to power supply malfunction
would be hard to diagnose.

you'd have to test this system with different models of all included components to see which of them, or none, could be causing an issue.