Cant boot mavericks, can't upgrade to new Yosemite off usb

[Fender73]

I recently did updates on my mackintosh A gigabyte mother board (z-77n wifi)with nividea gtx 660ti, i7 quad core processor. I get the loading circle of death on startup, i can't boot in -x, -f or graphics enabler=yes or no. so i made a new usb for osx yosimite off my wives mac book pro, but that won't work either cause apparently upgrading form mavericks to yoesmite u have to do erase a few kexts, which is fine but i can't boot into my mavericks to make the changes, and i don't have a back up bootable usb of mavericks and i couldn't find it to download on the App Store. I'm stuck now and don't know what to do, I've read people have similar issues after 10.92 but they all said they backed up from a time machine, i don't have this option. I'm a i totally screwed, should i count my losses and just reformat?

i have pro tools sessions and tons of important files, i can't afford to just reformat form disk utility, pls help

 

[Jithin.C.V]

I recently did updates on my mackintosh A gigabyte mother board (z-77n wifi)with nividea gtx 660ti, i7 quad core processor. I get the loading circle of death on startup, i can't boot in -x, -f or graphics enabler=yes or no.

Now are you able to boot into Mavericks with these flags??

so i made a new usb for osx yosimite off my wives mac book pro, but that won't work either cause apparently upgrading form mavericks to yoesmite u have to do erase a few kexts, which is fine but i can't boot into my mavericks to make the changes, and i don't have a back up bootable usb of mavericks and i couldn't find it to download on the App Store.

Personally i am not recommending an update between two major releases.

First try to resolve the booting issues of Mavericks and take backup of required datas. Then do a fresh install of Yosemite (This is only a suggestion from my side)

I'm stuck now and don't know what to do, I've read people have similar issues after 10.92 but they all said they backed up from a time machine, i don't have this option. I'm a i totally screwed, should i count my losses and just reformat?

i have pro tools sessions and tons of important files, i can't afford to just reformat form disk utility, pls help

What is happening while trying to boot into Mavericks??

Boot with flag -v and check where it is stuck.

 

[Fender73]

When I. Lot in -v it says this

 

[Fender73]

it say this
Loading Darwin 10.1
kernel cache ignored.
loading kernel /mach_kernel
can't find /mach_kernel
press a key to continue...

 

[Jithin.C.V]

it say this
Loading Darwin 10.1
kernel cache ignored.
loading kernel /mach_kernel
can't find /mach_kernel
press a key to continue...

What change you have done lastly?

 

[Fender73]

last thing i did was hit update button which i haven't done in 6 months or so, i know bad idea, i should of backed up, and then i tried reinstalling osx mavericks from my back up, it would install all the way only to freeze when u hit restart, tried this 3 time same result so i reformatted my usb and tried for yosemite, and now this where I'm left now

 

[Jithin.C.V]

last thing i did was hit update button which i haven't done in 6 months or so, i know bad idea, i should of backed up, and then i tried reinstalling osx mavericks from my back up, it would install all the way only to freeze when u hit restart, tried this 3 time same result so i reformatted my usb and tried for yosemite, and now this where I'm left now

Seems like /mach_kernel has been deleted in someway (Guess)

Boot into Yosemite bootable USB and through terminal check whether the mach_kernel is present on the Maverick's partition or not.

Do you have another empty HDD/SSD to install Yosemite??

 

[Fender73]

No I don't but It if it's the only way to get my pro tools back then I'll buy another ssd

Would switching to clover make the instal work and fix my problems maybe?

 

[Fender73]

Oh yeah, I found a way to boot up into Mavericks again, buts it's weird, I'm using the Yosemite usb and then hitting f12 to bot of Yosemite usb, then only way I can get into OS X Mavericks is typing -x but when Im at desktop I can run multi beast