Applies To:
  • CitectSCADA
  • Windows NT 3.51, 4.0

I am having problems with a Multi CPU computer running Windows NT. I don't know if the problems are being caused by the second CPU or some other reason. Is there some easy way to run under 1 CPU without removing the second CPU and re-installing Windows NT? 

I have seen some documentation that says you can switch Windows NT to run as a single CPU system with a command line switch in the BOOT.INI file. I have not tested this as I don't have a multi CPU computer. So I don't know if it really works. To do this add a new line to the BOOT.INI (by coping one of the existing lines) with the /onecpu option on the end as show below:

[boot loader]
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00"
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00 One CPU" /onecpu

This Knowledge base article is no longer relevant for users of CitectSCADA version 6.10 and higher as Citect32.exe has been modified into separate server and client components that can be configured to run on separate CPUs and/or processes. These modifications improve both the performance and stability of the CitectSCADA runtime environment. For more information, see KB Q4227.