Black Screen Mountain Lion Installation

[xTRICKYxx]

Hello, I cannot find anyone who has gotten around this yet.

I have a Lenovo Y550P and I have a feeling a wide variety of notebooks and desktops alike may experience this.

So, after trying several different USB thumb drives, re-downloading ML from the Mac App Store twice, and trying several different boot flag combinations, I give up. I just spent $20 on this and I really want to get it working.

Hardware:

i7-820QM
NVIDIA GeForce GT 240M
480GB Corsair Force 3 SSD
8GB DDR3 RAM

Issue: With or without -v flag, it boots the installation successfully (I believe) yet my screen is completely black. I have hooked up my laptop via HDMI to see if my external monitor would work.
I tried GraphicsEnabler=No -v -x PCIRootUID=0
Also, GraphicsEnabler=No -v -x PCIRootUID=1

I have replaced nearly every component on this machine except for the CPU and GPU to be compatible thus far. Here is a video of the final seconds on a verbose boot: Mountain Lion 10.8 UniBeast black screen installation - YouTube

I have made sure I followed all the steps in the guide.

Anyone with this similar issue or outside advice? I have gotten this laptop from 10.6.8 to 10.7.4 with relative ease and now I can't even boot the installer for ML.

 

[ssdp_20072]

did u try without GraphicsEnabler=No?

 

[xTRICKYxx]

Yes. Still a black screen.

 

[ssdp_20072]

Do u use a DSDT?? A dsdt with proper graphics edits and solve the problem.

 

[singj]

I had the same issue - the installation appeared to boot correctly, but then the display lost signal and went to sleep. If I pressed RETURN in the dark, the USB drive would get all busy so I'm pretty sure the system didn't actually hang.

I'm running the UEFI beta bios on my Gigabyte board so my installation was already devoid of any sort of graphics enabler - my 550Ti card was supported natively both in the UEFI BIOS and Lion.

I tried typing in simply PCIRootUID=0 before hitting ENTER to boot from the Unibeast installation drive, and the black screen problem went away. I didn't use any of the other flags / commands you list here.

Good luck!

 

[xTRICKYxx]

Thanks. I'll try that. My 240M is natively detected so its confusing.

PCIRootUID=0 by itself worked!!!! Thank you!!!! I swear I tried this by itself before....

 

[victor985]

thx

 

[hoogends]

Thanks guys

Had same troubles as poster.
PCIRootUID=0 by itself did the trick here too......

 

[jesperandreassen]

I had the same issue - the installation appeared to boot correctly, but then the display lost signal and went to sleep. If I pressed RETURN in the dark, the USB drive would get all busy so I'm pretty sure the system didn't actually hang.

I'm running the UEFI beta bios on my Gigabyte board so my installation was already devoid of any sort of graphics enabler - my 550Ti card was supported natively both in the UEFI BIOS and Lion.

I tried typing in simply PCIRootUID=0 before hitting ENTER to boot from the Unibeast installation drive, and the black screen problem went away. I didn't use any of the other flags / commands you list here.

Good luck!

PCIRootUID=0 worked for me as well!
Thank you very much singj

 

[Rezabrya]

Can I ask everyone how exactly I'm supposed to put this edit in? My screen also turns off on my Lenovo Thinkpad T430 when I try and boot from the Unibeast drive...