2.64 build slowing down computer

Upon installing the 2.64 release, my computer has been disturbingly slow, especially since it’s a pretty decent build and is more than capable of handling big loads. I’m just wondering if it’s the installer that’s causing the issues or the release itself?
The PC is fine now, I’ve done system restore a couple of times and it’s definitely caused by Blender, albeit no previous releases have caused this issue.