I have tried with the Windows 8 developers preview on my computer that was running Windows Vista earlier. It just took 20 minutes to install that completely and this is normal as all of my other friends had the same time while installing this. After completing the installation, I found that all the devices similar to wireless mouse was working well without any problem but it was missing the user notification or sound. I opened the device manager and found that there was yellow triangles in front of the things similar to the webcam. This problem is same for the external hard drive as well. It is working without any problem but it is not showing the notifications like "installing drivers etc". Is this just me who is getting this issue or there are other users with the same problem. Please reply me with some reason or solution to this problem.