While working on my laptop, I suddenly found my Windows PC screen flicker, go black, and then I saw the Blue Screen with the Stop Error – SYSTEM THREAD EXCEPTION NOT HANDLED (nviddmkm.sys). It can also occur for other drivers like atikmpag.sys, dxgmms2.sys, CMUSBDAC.sys, Idiagio.sys, iaisp64 sys, PCI.sys, Netwtw04.sys, etc.
What do you mean by System Thread?
A System Thread is the smallest sequence of a program that can be executed and managed independently by the Windows operating system.
Windows collected some information, and once that was done, my computer rebooted. Although I received on an otherwise stable system, this Stop Error is known to occur even during setup or upgrade times or due to system BIOS incompatibilities. This is what I did to resolve the issue.
Fix System Thread Exception Not Handled (nviddmkm.sys or atikmpag.sys)
First, make sure you have enough disk space. If not, use the Disk Cleanup Tool to remove junk files and free up disk space.
In my case, after the Error Code, you could see the name of a file. If a driver is identified in the bug check message, you should find out what the file is about. You could search for it on your computer and then check its Properties, or you could search on the Internet.
In my case, it was ‘SYSTEM THREAD EXCEPTION NOT HANDLED (nvlddmkm.sys)’, where at the end you will see a file name nvlddmkm.sys displayed. A simple search showed that it is an Nvidia display driver file. This means that it was this file that caused the Blue Screen.
In such cases you will have to disable the driver or check with the manufacturer for driver updates, depending n the situation. Since mine was the display driver, I decided to check if any updates were available. If it is a new Service that was added, disable it via services.msc and see if it helps.
It can also be caused due to the atikmpag.sys file which is the AMD ATI multi-vendor Kernel Miniport System Driver. In this case, you will have to update the atikmpag.sys AMD driver.
To update your drivers, from the WinX Menu, open Device Manager and expand Display adapters. Right-click on the Display Driver and select Update Driver Software.
If any updates are found, the wizard will download and install the driver for you. I decided to update both the Display adapter drivers.
Once the new drivers have been installed, restart your computer. This resolved my issue.
If the Blue Screen occurs at startup, you may need to boot Windows in Safe Mode and rename or delete the faulty driver. If the driver is used as part of the system startup process in Safe Mode, you must start the computer by using the Recovery Console to access the file.
The other thing you could do to resolve this Stop Error is to try changing video adapters. You could also check with your hardware vendor and see if any BIOS updates are available. If you have enabled BIOS memory options such as caching or shadowing, disable it. Ensuring that you have the latest version of Adobe Flash Player is something you may also want to do.
Read: How to fix DPC_WATCHDOG_VIOLATION Blue Screen.
This post gives you additional tips on fixing the Blue Screen of Death in Windows.