Windows 7 Processes

On starting my computer this morning I have noticed the CPU cooling fans running a little harder than I'm used to hearing when just using Firefox.

On looking at the task manager I have noticed that rather than sitting at the normal 0% CPU usage when idle a process labelled NTVDM.exe is sitting at a constant unmoving 25% CPU usage. A quick Google says it is an essential service and should not be terminated. But I have to confess I have never noticed it before and as already stated my processor usage normally sits at 0-5% when idle.

Any ideas please. I am deeply suspicious of this process despite what I see on the Googling.


Excellent Member
Microsoft Community Contributor
From what I can find, it seems this is a 16 bit process, possibly some type of virtual machine.

Do you know where you got it or any details about it? I do not show it on my system.

You might check msconfig.exe to see if you can uncheck it and keep it from starting up. Also, a good virus check may help.

Hi. Thanks for that. I have done a full virus scan and malware scan and found nothing. To my knowledge it wasn't there yesterday and oddly I can't find it in msconfig! I have ended the process and CPU usage returns to normal ie 0% on idle. But the process returns if I restart. However, when the process is terminated my machine appears to be functioning normally.


Excellent Member
Microsoft Community Contributor
If it isn't in msconfig under startup or services, it seems the next place to look for it is under the services.msc utility. If you find it, you can set it not to start.

In Task Manager, you can right click on the service and select properties. Maybe the details tab will show where it came from or what might be using it.

Are you sure you are not running some older type of program that might need the service. If you stop it, do any of your normal programs stop working?

If you can find it in the Windows\System32 folder or wherever, you might right click on it and have your anti-virus check it. It it might be a virus, and if your current anti-virus has not alerted, you may need to do a scan, or try another one to check. Some things like root kits are very hard to spot. There is a Security Zone forum here you might look into.

If it is using 25% of your CPU, it is either really doing something, or not working correctly.

If you can't find anything else, I like to use Process Explorer which you can get from microsoft. It will give more details about the different processes and what they might be doing.

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