No boot loader is installed in the MBR of /dev/sda.
Your Bootloader dont work.
That is not
the problem -- at least, not in the way you think! The computer in question is booting in EFI mode, and for that, the lack of BIOS boot loader code in the MBR of the disk is not diagnostic, since EFI places its boot code in a filesystem, not in the MBR of the disk.
Cyberz, I strongly recommend not
following Auphora's suggestion. At best it will be a waste of your time, and at worst it will actually make matters worse.
To fully understand the problem, it's necessary to know what you mean by "won't boot" and "not the Win8 part" in your original message. There are many ways in which a boot process can fail, with many different symptoms of failure. For instance, rEFInd might not present a Windows option; or selecting it might launch GRUB rather than Windows; or selecting it might produce a Windows boot failure message; and so on. Knowing the precise symptoms is important for diagnosing the problem.
If I had to guess, I'd say that rEFInd is producing a Windows entry, but selecting it launches GRUB. If so, what you need to do is to re-run the Boot Repair tool, click the Advanced Options item, check the Restore EFI Backups option, and proceed. This will undo some of Boot Repair's more reckless and unnecessary changes and enable rEFInd to detect and launch Windows. See this page
for more information. If I'm wrong in my assumption, you'll just have to post more details and await another reply.