ROG Strix Scar 16 / RTX 5090 – nvlddmkm.sys Crashes with External Monitor

[Slytha1808]

Hi guys,

Also posted this on ROG forum: https://rog-forum.asus.com/t5/gaming-notebooks/rog-strix-scar-16-rtx-5090-nvlddmkm-sys-crashes-with-external/td-p/1120221

Hardware

• Laptop: ASUS ROG Strix Scar 16 (2025)

• GPU: NVIDIA RTX 5090 Laptop GPU

• External Monitor: ASUS ROG XG27UCDMG (4K 240 Hz, HDMI 2.1)

- BIOS: v327 (latest)

• Windows 11: Fresh install, fully updated (twice)

• NVIDIA drivers: Latest from ASUS support (v576)

• Using G-Helper now in standard mode, optimus in Nvidia and Dynamic Bios. Got more issues in Ultimate and dGPU only.

Problem Description

Frequent BSOD with nvlddmkm.sys (SYSTEM_THREAD_EXCEPTION_NOT_HANDLED, exception code c0000094)

part of the dump(s)

Arg1: ffffffffc0000094, The exception code that was not handled
Arg2: fffff8057766f4fa, The address that the exception occurred at
Arg3: ffffd30f9a91d3a8, Exception Record Address
Arg4: ffffd30f9a91cbb0, Context Record Address

DUMP_FILE_ATTRIBUTES: 0x21808 Kernel Generated Triage Dump FAULTING_THREAD: ffffbf88f9b23080EXCEPTION_RECORD: ffffd30f9a91d3a8 -- (.exr 0xffffd30f9a91d3a8)ExceptionAddress: fffff8057766f4fa (nvlddmkm+0x000000000073f4fa) ExceptionCode: c0000094 (Integer divide-by-zero) ExceptionFlags: 00000000 NumberParameters: 0

Before reboot and crash:

Session "dc3a3596-71e1-45a3-b2ea-39ad5322fe51" failed to start with the following error: 0xC0000022

This event happens every 60 seconds:

Crashes occur: (Black screen, then "pc ran into problem")

• Using external monitor (HDMI 2.1) in Edge / Netflix or randomly (Funny thing i got it 3 times in a row when browsing to Netflix...)

• After closing games and doing something (switch from dGPU to iGPU probable cause)

• Sometimes immediately after display wake / GPU power state changes

• Internal laptop display havent tested much

• DSC, VRR / G-Sync, and monitor power state seem to influence crash frequency

• When rebooting the external display sometimes just wont start or boot, need to duplicate the screen and try several times before it wants to go.

Analysis / Likely Cause

NVIDIA driver encounters GPU power-state race when external monitor is connected, consistent with Zephkek GitHub ROG AML deep dive:

GPU enters impossible state: firmware insists OFF, Windows needs ON → driver thread blocks → 30s watchdog expires → BSOD

Contributing factors: (in my eyes possible)
High-res / high-refresh scenarios require DSC on HDMI 2.1 / DP 1.4

• HDMI 2.1 / DP 1.4 bandwidth limitations

• VRR / G-Sync active during DSC operation

• ASUS PowerSync firmware interaction

Windows / NVIDIA Settings (currently testing)

• HAGS (Hardware Accelerated GPU Scheduling) OFF

• G-Sync / VRR OFF

• DSC ON (Off only gets me 4K at 120Hz ofcourse)

• NVIDIA GPU: Optimus + Dynamic in Bios (dGPU + Ultimate gave me alot black screens)

• PCI Express Link State: max performance / disabled power savings

• CPU: set to 100% performance mode in power plan

• Turned off hardware acceleration in Edge / browsers / apps

• Custom fan curve applied for stable temperatures (Using G-Helper instead of Armory Crate)

BIOS / Hardware Settings

• BIOS GPU mode: Dynamic

• Latest BIOS v327 installed (this got my temps up quite a bit) Weird thing is this bios came out end of september, hoping this is not their "FIX" for the stutters and black screen BSOD problems MUX related

Monitor Settings

• ASUS PowerSync OFF

• Variable refresh rate and G-Sync disabled

• DSC ON

Other

• Fresh Windows 11 install

• Temperature monitoring: "normal" (<85°C) topping/spiking to 95-101°C but its not load-related

• Nvidia driver recommended by Asus (v576.65)

• Critical recommended drivers from Asus

LatencyMon:

Observations from LatencyMon

• ACPI.sys shows very high DPC routine execution times (~34,665 µs), which is extremely high.

• Wdf01000.sys (Windows Kernel Mode Driver Framework) also has high ISR times (~787 µs).

• Dxgkrnl.sys (Direct X graphics kernel) also has medium high ISR times (~910 µs).

High DPC / ISR execution times like this often cause:

• Buffer underruns in audio/video
• System stutters
• Potential race conditions with GPU power state, especially with NVIDIA DSC / HDMI 2.1

Combined with previous nvlddmkm.sys BSODs, these ACPI / WDF delays strongly suggest a power-state / driver handshake issue between the laptop, NVIDIA GPU, and external monitor likely caused by ACPI.sys / BIOS issues: Laptop’s ACPI implementation may be delaying GPU power-on or system wake events.

High DPC from system drivers: WDF or ACPI calls take too long, blocking GPU threads → could trigger the “impossible state” Zephkek described.

External monitor + DSC / HDMI 2.1: DSC + VRR / high refresh rates rely on fast DPC/ISR; any delay can trigger GPU driver timeout / BSOD.

Not sure if related but im also getting 20k "Display-External" Errors:

[Skyarbiter]

#14
NVIDIA Nsight Systems -
You can try using Nsight for detailed tracing of the entire system and identify the problematic component in the output, understand what is causing the false TDR triggers or driver crashes.

Also, check the system's behavior under load when there's no idle time, such as I/O operations from HID manipulators or simply playing music in a local player. Then check latency mon, as dynamic timer resolution incurs power savings during idle time, which is why stuttering is so severe, as it was in my case. But as soon as I start playing music, latency mon readings become perfect.

[Zephkek]

Hey can you send over the memory dump?

[Slytha1808]

@Zephkek I've send them to your email

[Slytha1808]

@Zephkek

If you have any new evidence regarding the ACPI matter, i'm also in contact with Intel:

https://community.intel.com/t5/Graphics/High-ACPI-sys-DPC-Latency-gt-34-000%C2%B5s-on-new-ASUS-ROG-Strix-Scar/m-p/1723506#M146507

&

https://community.intel.com/t5/Graphics/Intel-Gfx-Display-External-error/td-p/1721977

Regarding the massive "Intel-Gfx-Display-External errors":

Intel confirmed "I want to update you on the status of your case. We are currently investigating this display power management issue, and I can confirm that similar instances have been identified on related platforms."_

It seems this also might be related to the ACPI "story".

By the way, i just experienced a system hang instead of a BSOD:

Need a full memory dump now so they can investigate.

Posted in: https://rog-forum.asus.com/t5/gaming-notebooks/rog-strix-scar-16-rtx-5090-nvlddmkm-sys-crashes-with-external/td-p/1120221

---

Hello

My initial problem was a nvlddmkm.sys BSOD, which I traced to a catastrophic ~34,000µs DPC latency stall in ACPI.sys.
I have two major issues to report, both of which seem to point to this same ACPI/firmware root cause:
Issue 1: Chronic Intel-Gfx-Display-External Errors
Even when the system was "stable" (i.e., not hanging), I have been logging thousands of Intel-Gfx-Display-External errors in my Event Viewer. These errors have been happening constantly, even when the system would eventually crash with the NVIDIA driver BSOD. This suggests the underlying problem has been affecting the Intel iGPU driver all along.

The description for Event ID 10 from source Intel-Gfx-Display-External cannot be found... The following information was included with the event: 32.0.101.6790 (This is the Intel driver version)

Issue 2: The New System-Wide "Zombie State"
Today, I experienced a new, more severe failure that confirms the problem is a total platform stall.
• I started a benchmark. The dGPU (NVIDIA) on my external monitor engaged.
• The external monitor instantly went black.
• I waited 60 seconds, but this time, I did not get a BSOD.
• I pressed Ctrl+Alt+Delete, and my internal laptop screen (connected to the Intel iGPU) successfully turned on and showed the Ctrl+Alt+Delete screen.
• After logging in, the system was in a "zombie state." The external dGPU screen remained black, and the internal iGPU screen was active but non-functional.
• Any attempt to run a program failed. Taskmgr.exe hung. Browsers would not load. The PC would not reboot. I had to force a hard power-off.

The Event Viewer Evidence (From the Hang)

This hang filled my Event Viewer with errors, proving a system-wide collapse of the hardware communication layer (WMI).
Complete WMI Service Collapse: I am seeing hundreds of WMI query failures with ResultCode = 0x80041032 (Call Canceled) and PossibleCause = Throttling Idle Tasks.

Applications are trying to query basic hardware information and the system is failing to answer:
• Operation = Start IWbemServices::ExecQuery - ROOT\CIMV2 : SELECT Caption FROM Win32_VideoController
• Operation = Start IWbemServices::ExecQuery - root\cimv2 : SELECT SerialNumber FROM Win32_BIOS
• Operation = Start IWbemServices::ExecQuery - ROOT\CIMV2 : SELECT Name FROM Win32_Processor
• Operation = Start IWbemServices::ExecQuery - root\WMI : SELECT InstanceName, VideoOutputTechnology FROM WmiMonitorConnectionParams

System Hangs as a Result: This WMI collapse directly caused the "zombie state" I experienced:
• The program Taskmgr.exe version 10.0.26100.6725 stopped interacting with Windows and was closed.
• An error occurred when transitioning from DesktopLocked... (ErrorCode 0x8007139F)
• ...

Conclusion

This single, chronic stall is:
• Causing the Intel iGPU driver (Intel-Gfx-Display-External) to log thousands of errors.
• Periodically causing the NVIDIA dGPU to hang or BSOD.
• Causing a complete Windows WMI service collapse, preventing it from querying platform hardware like the CPU and BIOS.

Im also "in contact" with intel:

High ACPI.sys DPC Latency (>34,000µs) on new ASUS ROG Strix Scar 16 (2025) - Causing 0x7E NVIDIA BSO - Intel Community

Other guys on Intel fora are also experiencing the massive amount of intel external-display errors:

Intel-Gfx-Display-External error - Intel Community

Intel confirmed: "I want to update you on the status of your case. We are currently investigating this display power management issue, and I can confirm that similar instances have been identified on related platforms. "

Intel is asking for a complete memory dump. I just activated this, and now need to try and get the BSOD back so a full memory dump is created. I will upload the memory dump and also send this to you.

Regards,
Kevin

[Slytha1808]

@Zephkek

Is Asus is still fixing their code/firmware as of your knowlegde, because this seems to have gone quiet.

Regards,

Kevin

[ianblue55]

Hi, just wanted to share my simple workaround on my laptop (STRIX SCAR 16 with RTX 5080) since we don't have solution or the issue cannot do anything fix it,

• Set to "Ultimate" on G Hepler to use dGPU only. (Auto HDR is activated on Windows Settings app).
• As I plug in my laptop all the time, I have set my laptop never sleep when plugged-in.
• I set never turn of my screen as well when plugged-in. (my laptop will restart when my screen is off after amount of time when using Ultimate mode (dGPU). Checked it was the "watchdog" BSoD with the tool "bluescreen viewer" after my laptop restarted. Then I was lead to here after researching about issue.)

That's all for the workaround. It may not applicable to all users as we may have different using habit.

Sharing my laptop symptoms:

• If I set the GPU to Eco/ Standard/ Optimized, which make the laptop screen to use integrated graphics, my laptop will stutter every 30 to 60 seconds randomly on light task such as web browsing and heavy task like gaming. I can notice my laptop is stuttering by moving my cursor and in the middle of gaming. So using integrated graphics is not usable to me. However if my laptop screen is turned off after idling time of 1 min, it will not restart, BSoD did not trigger when my laptop is using integrated graphics.

• If I set to dGPU mode on my laptop, the stuttering issue is gone. However, my laptop will restart after my screen is turned off (not sleeping) after 1 min of idling time and triggered BSoD then the laptop restart itself.

My laptop is currently set to never sleep and never turn off screen while plugged-in as workaround. Actually, I want my screen to be turned off after idling time like 5 min because I dont want it to be turned on all the time when I leave my laptop in the house.

I tried to comment on the thread by OP (Slytha) on ROG forum but failed as the thread is closed. Hope this issue will be fixed soon.

[Slytha1808]

Hi Guys,

One thing that helped me mitigate the black screen and stutter issues, is download "Power settings explorer"

In there enable:

• Processor Idle demote threshold

• Processor idle promote threshold

Then go to your energy plan - Advanced Settings - the new options become available

Set both Plugged in on 100% (keep battery one normal for better battery if needed)

This helped my stuttering, latencymon gives better results and so far so good for weeks on the black screen issues.

What this does is disables the processor's ability to enter deep power-saving states (C-States).

Result: Your CPU will run a bit hotter, consume more power when idle.

Benefit: You eliminate "wake-up latency." This is useful for real-time audio processing (DAWs) or ultra-competitive gaming where even a microsecond of delay caused by the CPU "waking up" from a sleep state can cause audio crackles or stuttering. Or when having an Asus laptop with latency issues or black screen issues with 2nd monitor etc

Be sure to check temps and use an IETS cooler or some kind to keep ya laptop cool

Oh and one tip, in GPU intensive games set manual mode in armoury crate and set PL1 to 35W, and PL2 to 55.

I have tested alot of games and this keeps the CPU cool, and doesnt lower frames because the CPU is efficient on these wattages.

My specs:

Laptop: ASUS ROG Strix Scar 16 (2025)
GPU: NVIDIA RTX 5090 Laptop GPU
CPU: Intel Ultra 9 275HX
External Monitor: ASUS ROG XG27UCDMG (4K 240 Hz, HDMI 2.1)

Hope this may help :)

Meanwhile ive chatted alot with Asus support, but all i get is "they can not reproduce".

Other settings i got enabled or disabled:

Recommended:

• All usb controllers disabled sleep in device manager, go through all usb controllers and in properties - power management disable the "Allow the computer to turn off this device to save power"

• Be sure to have dynamic gpu mode in bios (don't use dGPU only), and use optimus in nvidia control panel. (defaults when setting dynamic in bios). dGPU (ultimate mode) has alot of issues atm, using this mode will result in white snow on screen, low GPU usage, audio stuttering...

Optional:

• Armoury Crate manual mode: Set PL1 to 35W, and PL2 to 55W.

• Fan curves in manual mode 70% above 70 degrees with an IETS GT cooler. (running at 1200 RPM), adjust to your own needs.

• Undervolt -30mv in Bios (disable intel TXT, then set the undervolt) -> lowers temps by 3-5°C, and increases performance and benchmark scores by alot.

Current temps:

• Running BF6, Arc raiders, Hogwarts Legacy without issues on average 73 to 80°C. No more spikes to 100 because of the PL1 and PL2.

Oh yeah and i am running the latest nvidia drivers 591.59.

Some forum posts still ongoing:

https://rog-forum.asus.com/t5/gaming-notebooks/randomly-losing-all-usb-devices/m-p/1131307#M12832

https://rog-forum.asus.com/t5/gaming-notebooks/asus-rog-strix-scar-2025-g18-5090-external-monitor-issues/m-p/1131358#M12838

Intel display external issues:

https://community.intel.com/t5/Graphics/High-ACPI-sys-DPC-Latency-gt-34-000%C2%B5s-on-new-ASUS-ROG-Strix-Scar/m-p/1723506/thread-id/146507

Regards

[KrisNinja]

I had experienced black screen and stuttering many, many times when playing games that stress GPU heavily. It was so annoying, as in fact I couldn’t play, as game and laptop hang (i.e. black screen and restart after 30-60 seconds) after 1 or 2 minutes after launching a game.

However, many kudos to @Slytha1808 for his settings as I used them on my laptop on 18th of December and it resolved the black screen and stuttering issues for me. No more black screen and system freeze, so far.

[Slytha1808]

Hi KrisNinja,

Thank you for confirming this also resolved your black screen and stuttering issues.

It seems to be having something to do with processor's ability to enter deep power-saving states (C-States).

I have made a reply on the posts in the Asus Rog forums and also send this to the moderators (Scone & Falcon)

https://rog-forum.asus.com/t5/gaming-notebooks/randomly-losing-all-usb-devices/td-p/1091235/page/22

https://rog-forum.asus.com/t5/gaming-notebooks/asus-rog-strix-scar-2025-g18-5090-external-monitor-issues/m-p/1131450#M12847

---

Support has previously stated that engineering "cannot reproduce" the issue. I have most likely identified the specific root cause and a reproducible solution. The instability is most likely caused by a defect in the ACPI implementation regarding Processor Idle (C-State) transitions and maybe USB Selective Suspend (not sure)

Step 1 (ACPI C-States): Using Power Settings Explorer, I exposed the "Processor idle demote/promote threshold" options. Setting these to 100% prevents the CPU from entering deep C-States.
Result: Latency spikes disappear (confirmed in latencymon), audio stutter stops, and black screens cease.
Step 2 (USB Power): Disabling "Allow the computer to turn off this device" for all USB Controllers in Device Manager. (optional)
Result: Most likely prevents a USB bus collapse that might previously accompanied the black screens or some kind.
Additional Firmware Defects (dGPU Mode) I must also report that the dGPU (Ultimate) Mode is currently functionally broken on this BIOS.

Visual Artifacts: White static/snow appears on the internal display (initialization failure).
Performance: GPU usage drops to 60-80% causing severe FPS loss compared to Optimus mode.
Please escalate this to the needed teams. The solution is not to force users to disable power-saving features permanently. The solution is for ASUS to fix the ACPI C-State and USB Power tables and the dGPU mode in the next BIOS update so the hardware can transition power states without crashing the platform.

This is all my eyes of the solution.

"Disclaimer: I am a user, not a developer or ASUS engineer. These findings are based on my personal testing and troubleshooting to resolve stability issues on my own unit. I am not responsible for any potential damage or issues that may arise from applying these power modifications to your own hardware; proceed at your own risk." (As i do think it is safe for these changes to make, as long as you monitor your temps at start).