Windows 7 would not dual boot on vaio with windows 8 preinstalled UEFI

Hello
Spent about literally hundred days. Trying to dual boot windows 7 on my UEFI vaio pre installed with windows 8. I tried to follow almost all the forums on the Internet. Created bootable usb which gets stuck at starting windows and used a dvd which the vaio does not recognise. When choosing legacy boot on bios then the problem comes that my hdd is not mbr and I am not in a position to format and delete everything due to important files. Pleas help me how do I install windows 7 on this Vaio as there is no guide for this specific platform. Thanks

As far as the BIOS goes the VAIOs are very restrictive. I was fighting with a VAIO for several weeks until I RMAd it. You may want to try running the Win7 in a virtual partition.

Virtual OS Tutorial - Install, Setup and Operate

Right, virtual is not for gaming. But that does not bother me because I am a strict anti-gamer.

Hi,
I believe you'd have to install win-7 first then add win-8 after if it's even possible.

Hi,
I'm sure you would run into the same conflict installing Vista if 8 is already installed
You can have uefi bios and install Vista or win-7 just so ahci compatibility is enabled.
Secure boot would need to be disabled but CSM needs to be activated

OS Type has to be anything other than UEFI only.

Fast or quick startup needs to be disabled.

But most of all win-8 has to be installed after Vista or 7 is installed.
And that is unless the manufacture of the machine has not locked out win-7/ Vista installs.