Hidden Content
Microsoft's most recent Windows 10 update is causing a CPU spike upon startup, and the culprit might be Cortana.
As Windows Latest reports, the updated version of Cortana is causing processors to spike by 30 to 40 percent and hog system memory.
On Microsoft's Feedback Hub, one user said Cortana was using approximately 200MB of memory constantly. Another saw it running "above 35% CPU usage and 150 MB memory as reported by Task Manager, for at least one day now."

The update was tested by Windows Insiders in the Release Preview Ring before release, as usual, and the Cortana problem was flagged. But "the reports appear to have been ignored because they weren't upvoted enough," Windows Latest says.
Some users claim that deleting a Registry key to prevent the Start menu from sending local searches to Bing resolves the problem. But this involves editing Windows' Registry, the database that stores configuration settings for Windows components and applications. If you have the know-how, go to the Registry (by pressing Windows + R typing in 'regedit'), open HKEY_CURRENT_USER, then Software\Microsoft\Windows\CurrentVersion\Search, find an entry called BingSearchEnabled, and change the value to 0.

Those who don't want to edit their Registry can uninstall the update by going to Settings > Update & Security > View update history > Uninstall updates.