This year's freebie at Microsoft Build 2015 conference is the HP Spectre x360 laptop, which came with Windows 8.1 installed. The idea is to take it away and update it to Windows 10 to allow all us developers to get to grips with the new features of Windows 10, VS2015, etc.
Like many other geeks I've never been particularly happy with the sort of crap you get pre-installed on laptops. Even when you don't get true bloatware, there are usually things like replacement Wifi management apps or manufacturer
So, that meant starting from scratch, wiping the windows 8.1 partition and installing Windows 10 straight from a USB stick. Install went fine, but there were a lot of unrecognized devices in device manager once it had finished.
What's missing? Where are the downloads?
Intel SMBus Controller and other Intel devices
https://downloadcenter.intel.com/product/1145/Intel-Chipset-Software-Installation-Utility
HP Wireless Button Driver
ftp://ftp.hp.com/pub/softpaq/sp58501-59000/sp58720.exe
Audio Driver
http://ftp.hp.com/pub/softpaq/sp70501-71000/sp70653.exe
Intel Virtual Buttons Driver
http://ftp.hp.com/pub/softpaq/sp70001-70500/sp70349.exe
This might not be entirely complete, as I have put it together from memory and the things I have left in my download folder after performing the process. I don't feel like going back and installing agian just now to check :)
There was one other driver missing, but that got picked up by asking it to update and automatically find drivers for my device.
You can find other downloads for the machine here
http://support.hp.com/us-en/drivers/selfservice/HP-Spectre-x360-Convertible-PC-Series/7527520/model/7791778#Z7_3054ICK0KGTE30AQO5O3KA30R1
