It was not svchost at all but the app that uses svchost (that's a host!) I know a few causes but given so little detail my guesses would be worse than your google. Tell more.
Bob
When i start my computer or connect to my internet , the scvhost process uses all my cpu for 10 minutes or so , then it drops to 50% , and eventually stops. And sometimes it starts using 50% cpu randomly .
My windows automatic updates option is off , i googled my issue and apparently this should be the solution , but it's not.
Chowhound
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GameFAQs
GameSpot
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