Yes, they don't provide the drivers now, I think they will not provide the drivers in the future too. I guess you should have the either win7 or win8.1, so you should update the all the windows updates before you do the win10 upgrade.
Also you should disconnect non-essential devices like the 2nd HDD, add-on card, disable your antivirus utility, win10 will install all the drivers for you. After upgrading, you should go to AMD or Nvidia site to download and install the GPU driver.