Yosemite no longer boots after GTX970 install

[Zukabak]

Hi Folks..

You know when you just wished you'd left things alone?.. well that..haha

Ok, I had (until this morning) a fully working Customac, using an nVidia GTX760.
I've just upgraded to a GTX970(Haswell chip) as apparently these are now fully supported with the new nVidia webdrivers etc.

As expected, it wouldn't boot at first, so I had to use the "nv_disable=1" flag in order to get it to boot. I then installed the webdrivers, selected to use the nVidia drivers via the toolbar and rebooted. It seemed to a long time to boot (along with a new TM86 boot logo?) but did boot and everything appeared to cool.
I noticed via the nVidia update tool that there was a newer version of the webdrivers, so allowed it to update them and reboot. This appears to have broken things.. as it now boots to a 'no entry' logo.

Running the verbose logging, it appears to be hanging looking for the root device (I use an SSD) so I assume it's changed my plist somehow, as I vaguely remember having to delete a kext from the console to get it to work a while back.

Unfortunately, it looks like the only way to edit that is to use the USB bootloader to access the system console, but that just crashes with the following error:



So basically, I'm stuck.. can anyone help?

 

[Amylowellow]

aren't you supposed to have nvda_drv=1 as boot args? i only see kext-dev-mode=1 there...?

edit: nm...didn't realize your screenshot comes from booting from USB not your main SSD...sorry

 

[YngveN]

Hi Folks..

You know when you just wished you'd left things alone?.. well that..haha

Ok, I had (until this morning) a fully working Customac, using an nVidia GTX760.
I've just upgraded to a GTX970(Haswell chip) as apparently these are now fully supported with the new nVidia webdrivers etc.

As expected, it wouldn't boot at first, so I had to use the "nv_disable=1" flag in order to get it to boot. I then installed the webdrivers, selected to use the nVidia drivers via the toolbar and rebooted. It seemed to a long time to boot (along with a new TM86 boot logo?) but did boot and everything appeared to cool.
I noticed via the nVidia update tool that there was a newer version of the webdrivers, so allowed it to update them and reboot. This appears to have broken things.. as it now boots to a 'no entry' logo.

Running the verbose logging, it appears to be hanging looking for the root device (I use an SSD) so I assume it's changed my plist somehow, as I vaguely remember having to delete a kext from the console to get it to work a while back.

Unfortunately, it looks like the only way to edit that is to use the USB bootloader to access the system console, but that just crashes with the following error:

View attachment 141214

So basically, I'm stuck.. can anyone help?

You have to delete the AppleTyMCE.kext and AppleGraphicsPowermanagent.kext. (it may have the word driver in there, but dont remember where).

 

[Zukabak]

I've managed to sort it.. thought I'd mention the fix in here in case anyone else has the same issue and hits this thread via a search.

Booting from USB was a no go, as per the screenshot.. however I could boot if I used the -x 'safe mode' flag. Once in, I downloaded the latest version of Multibeast and simply created a new profile etc. Saved and installed, then rebooted.. all good!! *Phew*
I've absolutely no idea why installing the new webdrivers seemed to overwrite my bootloader plist though, which is a bit worrying. Obviously just needed the '3rd Party SATA' option reinserting.