The drivers page appears to only have drivers for Windows 8, 8.1 and Ubuntu. Installing it may cause some of your hardware to be unsupported. If you want to give it a shot, I would create an external recovery image, perform the downgrade and if you can't get the drivers you require from other means (Windows Update, HW Manufacturer, or Customer Drivers), than you can always restore your OS from the backup.
Drivers page:
http://h10025.www1.hp.com/ewfrf/wc/softwareCategory?cc=us&lc=en&product=5371337
Create a USB recovery drive:
http://windows.microsoft.com/en-us/windows-8/create-usb-recovery-drive