Si sur votre PC vous vous rendez compte que le processus svchost.exe consomme toute votre RAM, faite un clique-droit dessus puis "Accéder aux services". Là vous être sur la page des services avec tout ceux contenus dans le processus svchost.exe en surbrillance. Si vous avez le service wuauserv dans le liste, c'est Windows Update, faut installer le fix :

Update (4/30/15):  A patch is apparently in development that will address this issue.  There is information here regarding the update:

http://blogs.technet.com/b/configuratio … tatus.aspx

The post title is a bit misleading, as the patch should apply to the Windows Update client.

Update (6/3/15):  The patch has been released!  I have marked the post that links to the patch as the answer, and a couple posters have reported positive results after installing the following update:

https://support.microsoft.com/en-us/kb/3050265


Update (8/4/15):  The original fix (3050265) has been superseded by the following:

https://support.microsoft.com/en-us/kb/3065987

Update (11/11/15):  This is the latest release of the update agent:

https://support.microsoft.com/en-gb/kb/3102810