Just got an ASUS X501U with Window 8 preinstalled (can't be Windows 8, it don't have multiple windows!). Ye gods, what a cock up, this is a notebook with mouse and keynoard, not a tablet. So, downgrade to Windows 7. Asus support say not possible. Hmm, thats a challange if ever I heard one.
Actually the only thing stopping you downgrading is you have to supply your own copy of Windows 7 64 bit (32bit will not suffice). If you have one on disk then it is 'simply' a case of downloading all the Windows 7 x64 drivers that are available on the Asus web site, wiping the disk and clean installing Windows 7 x64, install the drivers and then let Windows 7 x64 update itself over and over again until its all finished. Presto, a nice new X501U with Windows 7 x64 as you could have purchased pre-Window 8 launch.
However, the brick wall I initially hit was that the X501U has no built in DVD drive so I had to use a USB external one and I could not for the life of me get the BIOS to detect it and boot from it. After much guess work I finally sorted it out.
First, download all the drivers from the ASUS site as you will initially be unable to connect to the internet without them once you have installed Windows 7 x64. Put them on a USB stick ready to use later.
Secondly, the two USB ports supplied are NOT equal. The one on the left next to the power jack is USB 2, the one on the right is USB 3. The BIOS does not recognise the USB 3 port when I plug the DVD drive into it. Switching to the left one sorted that out!
Then you also need to change some BIOS settings to get the BIOS to detect and boot from an external USB DVD drive. Boot the notebook and press F2 immediately as many times as needed until the BIOS comes up. In the Advanced menu make sure 'Legacy USB Support' is enabled. In the Boot menu enable 'Launch CSM'. Now make sure your USB DVD drive is connected to the USB 2 port on the left hand side with the Windows 7 x64 install disk up and running in it. Now go to Save & Exit menu and Save and Exit.
When the X501U restarts it will now see the USB drive and make it available for booting. It will probably, however, still boot to Window 8 as you need to re-enter the BIOS to configure the boot sequence. Return to the BIOS as described previously and then go to the Boot menu. You should now see a 'UEFI DVD' or similar available in the list of boot options. The other 2 that are there by default are Window 8 and the recovery system. Go to 'Boot Option #1', press enter and then select the UEFI DVD entry and press enter. This will make the DVD the first port of call when booting. The other two entries will then be shifted down.
Save and Exit from the BIOS and when you reboot you will be asked to press a key to boot from the DVD. Do so and then you are ready to install Windows 7 x64.
Now, I tried several times to install Windows 7 x64 in volume 3, overwriting Window 8, without success. The disk is formated as a 'GPT' disk and it seems very sensitive to how its partitions are handled. Maybe some one else will solve this one but I eventually decided to throw away the recovery options and deleted every partition available using the Windows 7 installer until I had a clean disk and then I created a new 100GB partition to install to. The installation warns that it will create some other partitions to support the UEFI/GPT way of doing things to which I agreed and then the install went through unchallenged and without a hitch. I then created another partition for the remaining space using the Windows disk manager.
Once in Windows 7 x64 get those Windows 7 64 bit drivers you download earlier onto a USB stick and copy them on to the notebook. Install the LAN drivers first and you will quickly find the internet comes up working okay. Plough through all the other drivers to get full functionality. Note there are sometimes two sets of drivers for different hardware. Just install everything, those that are not required will abort when they can't find the hardware.
Phew, hope that all makes sense. Would be nice if Asus just gave us the option of buying a Windows 7 system in the first place (as we could prior to October).