Yosemite freezes at boot "Loading Operating System"

[eblitz]

I have upgraded my Mavericks machine to Yosemite on a new clean SSD drive...several times. Each and everytime I use the DSDT file for my Gigabyte motherboard GA-Z68MX-UD2H-B3 in Multibeast and it casues the machine to freeze at the white screen with Apple logo. I have tried many times with various bootflags to boot up into system but unfortunately I can never get it to boot up.

Currently, I have the system up and running without using Multibeaast but there are key things not working such as the USB ports on my Apple LED 27 inch monitor plus the camera, iCloud authentication etc.. If I reboot the machine I get the message "Loading Operating System" and it freezes.

I am using the AMD Radeon HD6870 video card. Any help to get me passed these boot issues is greatly appreciated!

Thank you!

 

[P1LGRIM]

I have upgraded my Mavericks machine to Yosemite on a new clean SSD drive...several times. Each and everytime I use the DSDT file for my Gigabyte motherboard GA-Z68MX-UD2H-B3 in Multibeast and it casues the machine to freeze at the white screen with Apple logo. I have tried many times with various bootflags to boot up into system but unfortunately I can never get it to boot up.

Currently, I have the system up and running without using Multibeaast but there are key things not working such as the USB ports on my Apple LED 27 inch monitor plus the camera, iCloud authentication etc.. If I reboot the machine I get the message "Loading Operating System" and it freezes.

I am using the AMD Radeon HD6870 video card. Any help to get me passed these boot issues is greatly appreciated!

Have you installed the UEFI BIOS : Link

You shouldn't need a DSDT with that.

 

[eblitz]

I will give that a try, thanks!

 

[eblitz]

I have tried to update BIOS but I get a BIOS ID error and cannot move through the BIOS update process....help?