When I went onto the HP site I entered the product id, serial number etc of my laptop so it knew exactly what drivers were compatible to my system. (Windows version, processor, etc etc).
But it's no drama to get the drivers you suggested above so I'll just do that. Do you have a preferred site?

I keep getting confused and/or forgetting if I'm x64 or x86. Im pretty sure im x64.

How do I find out if I've got USB 3?