Hi Xaxxus! Good news for you. Windows 8 has our Rampage 3 Extreme drivers out of the box. You won't be needing to go to the site to download anything. You get your chipset driver, LAN, bluetooth, USB 3.0 (native support!!) etc... Realtek always updates their drivers, so they're really the only one you need to download. The Bluetooth driver on the ASUS site still works, or you can use Win8's built in driver (I did that because it's more compatible with my phone.)
Well, I did email ASUS a while back, they said they would update the driver page... apparently this wasn't so as I emailed them again and they said "No, sorry." It's ok because Win8 does install them for us and they work very very well, if not, better than what we were using before.
Sad to say, utilities are definitely not supported. No TurboV evo, monitoring etc... You'll get an ACPI error stating the model is not supported. BIOS always was a better solution anyway.. Real Temp is a good alternative for monitoring. I wish ya luck pal. R3E is still as solid as ever and Win8 handles real well on it, if you can put up with the UI changes 😛 I sure did.