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If your CPU usage is inexplicably spiking, try installing this optional Windows 10 update

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The next cumulative update for Windows 10 is now available to download in preview form, and installing it could make your PC run faster. That is, if you've been experiencing abnormally high CPU usage as of late, in which case this update may be the cure for what ails your PC.

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At issue is what appears to be an undocumented bug in Windows 10. Or unacknowledged, I should say, because as Windows Latest noticed, Microsoft's Feedback Hub is rife with complaints of high CPU usage with little rhyme or reason as to the cause. The site says it could be due to a bug triggering what's called a 'race condition' in Windows 10.

"A race condition occurs when two threads access a shared variable at the same time. The first thread reads the variable, and the second thread reads the same value from the variable. Then the first thread and second thread perform their operations on the value, and they race to see which thread can write the value last to the shared variable. The value of the thread that writes its value last is preserved, because the thread is writing over the value that the previous thread wrote," Microsoft explains.

The complaints have lessened considerably since Microsoft made available its KB5001391 update around a week ago. This is classified as a "cumulative update preview for Windows 10 version 20H2," meaning it contains some of the fixes that will be included in this month's Patch Tuesday update scheduled for May 11 (cumulative updates arrive on the second Tuesday of every month).

Microsoft's support page for KB5001391 (opens in new tab) does actually reference a race condition fix related to this update, albeit just for Windows 10 version 2004. It also mentions an "issue that causes Isass.exe memory usage to grow until the system becomes unusable," as well as several other bug fixes.

There's no guarantee this preview update will curb your system's high CPU usage, if that's something you're experiencing. However, it's certainly worth giving it a shot.

To install it, head to Windows Update and see if KB5001391 is available in the section labeled Optional quality update available. If you don't see it, mash the Check for updates button, and see if it appears.

Otherwise, just hang tight. There are no security patches in this preview update, and it will be doled out in its entirety to Windows 10 users via Windows Update next week.

Paul has been playing PC games and raking his knuckles on computer hardware since the Commodore 64. He does not have any tattoos, but thinks it would be cool to get one that reads LOAD"*",8,1. In his off time, he rides motorcycles and wrestles alligators (only one of those is true).