Windows 10 CPU spikes? 1903 update brings fixes but also high usage issues

Some users of Windows 10 version 1903 are experiencing CPU usage spikes after installing last week's optional cumulative update. 

The update, labeled KB4512941, addressed the Visual Basic 6, VBA, and VBScript problems that Microsoft fixed in earlier versions of Windows 10, Windows 7, and Windows 8.1 a few weeks back. 

It also addressed over two dozen other key non-security bugs that made it an appealing optional update to install. However, some of those who grabbed the optional August 30 update for version 1903 have now started complaining of high CPU usage immediately after installing it.  

SEE: 20 pro tips to make Windows 10 work the way you want (free PDF) 

Multiple Windows 10 1903 users on Reddit who report CPU spikes after installing the update believe the issue is caused by the Cortana process SearchUI.exe. Some users reported resolving the issue after disabling that process. Others have resolved it by uninstalling KB4512941. 

The number of comments on Reddit and Microsoft's answers forum suggest the problem isn't that widespread. 

However, as spotted by Windows Latest, some Windows Insiders did report CPU consumption as an issue in Microsoft's Feedback Hub when the update was briefly in testing with Windows Insiders. 

Microsoft released KB4512941 with the 1903/19H1 preview build 18362.329 on Thursday, two days before releasing it to the public. 

This CPU bug is exactly the type of low-volume issue Microsoft is trying to catch in Feedback Hub. The company recently refreshed Feedback Hub to address the "trickier" problem of upvoting problems versus feature requests because problems aren't driven by popularity. 

But probably due to the Windows 10 1903 update spending such a short time in preview testing, there were only a handful of reports, which didn't get many upvotes.    

SEE MORE: Windows 10: We're now gearing up for 1909 with new throttled release, says Microsoft

Windows Insider testers reported seeing CPU spikes of between 30% and 40% in Task Manager as well as higher memory usage. Additionally, Feedback Hub reports mirror complaints that the Search button next to the Start Menu isn't working.    

More technical users have suggested editing registry keys to resolve the issue, but for most users the simpler and safer option would be to uninstall the update if it's causing CPU problems. 

Microsoft hasn't acknowledged the CPU issue on its release notes for KB4512941. 

More on Microsoft and Windows 10 updates

• Windows 10: We're now gearing up for 1909 with new throttled release, says Microsoft
• Microsoft: These Windows 10 updates fix broken Visual Basic apps but not for 1903
• Microsoft warns Windows 10 admins: No more patches for 1703 after October 9
• No more buggy Windows 10 updates? Microsoft makes it easier to flag early flaws
  
• Windows 10 recovery: Microsoft borrows Apple's Mac cloud reinstall feature
  
• Microsoft releases two new Windows 10 19H2 test builds
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• Windows 10 19H2: If you're on 1903, expect 'far faster' update, says Microsoft
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• Windows 10 updates: We're now using AI to push 1803 users to 1903, says Microsoft
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• How to delete the Windows 10 paging file on every shut-down TechRepublic
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