Unable to access BIOS, laptop with UEFI, Ubuntu 14 installed (Dell XPS13)

[arifgoh]

Hi. I have an ultrabook Dell XPS 13 with pre-installed Windows 8. One day, I accidentally overwrote win 8 on my laptop (which normally has backup) and I installed Ubuntu 14 straight away as I was in the middle of finishing my assignments. After that, when I tried to install a Win 7 from usb, I failed as I can't access to the BIOS of my computer to change the boot preference. Maybe there's another way to boot as this laptop is equipped with UEFI, I don't know.

Do you by chance know how to troubleshoot this problem?

Thanks in advance

[Geek-9pm]

Do you by chance know how to troubleshoot this problem?

Yes, you contact the maker of your laptop.
You say the  PC is a ultrabook Dell XPS 13 with pre-installed Windows 8.
You overwrote Windows 8 with a auto install of Linux, namely Ubuntu.
Dell support is familiar with this kind of problem and they are in the best position to help you.
www.dell.com/support

When you contact Dell, you will need the serial number.