Jake Lo

in the clover menu press the space button and select boot without caches then hit enter. it should boot in verbose mode and show where it is getting stuck.

do you see the Yosemite disk during boot? Since you have it installed previously, can you restore the files prior to using Herve's files?

You need to replace them in /System/Library/Extensions. You might want to back up the original first.

Where did you get the source file to create the Installer?

Check here too.

See here.

Can you see the Yosemite partition from your running Mavericks? Bootpack from Herve's guide are for Mavericks, some of the kexts might not work on Yosemite.

Make sure you have ACPIBacklight.kext installed for the brightness. For sound check your old DSDT, is it the same layout id?

Thanks Herve. Didn't notice that. New thud sound is not as nice as chirping from Mavericks.

Yes, but might need a different DSDT. Get it from here. Generate your own SSDT from the guide.

Which graphics card is listed when you use GraphicsEnbler=Yes or No?

Try adding AtiConfig=Langur, GraphicsEnabler=Yes/No to org.chameleon.boot.plist If ATI 5470m is not supported, you could try disabling it and use the 1st Gen Intel HD graphics. To boot with that, you'll need to remove AppleIntelHDGraphics* To get full QE/CI with that, you could read more about it here.

Awesome! Enjoy

Update! Found a workaround to fix the internal display for NVS4200M (Optimus Disabled) See here.

After a lot of trial and error, I finally got the NVS display working with the original DSDT. I guess Apple has made a lot of changes to their video kexts since 10.9.2 ( Nvidia and Intel). I went back and tested all the installer from 10.9.0 -> 10.9.5 and 10.10.1. That last version that the internal display shows up is 10.9.2. So I rolled back 10.9.5 installer nvidia files with 10.9.2 and it worked and also worked on 10.10.1. Files I replaced are: NVDAGF100Hal NVDAResman NVDAStartup (optional- works without roll back) So far I haven't see any issue, but will need further testing. Attached are the files if you don't have 10.9.2. Also included is an updated DSDT to fix the Battery issue and IOAHCISerialATAPI_Injector.kext to fix the DVD Player error. NVS4200m.zip

Check thread here. Lots of information.

That should work without any issue if you follow the guide closely. Which one did you follow? Optimus enabled or disabled?

Which thread did you get the kext?

Did you install it to /System/Library/Extensions and then repair cache and permission?

Follow the instruction under Troubleshooting.

it should be (plus not minus) sudo chmod +x ssdtPRGen.sh

Does your Yosemite SSD shows as RAID with a Lion icon?

See guide here. Bootpack is available in post #3

Can you list what's not working so we recommend kexts you'll need?

Strange, that DSDT works for me. What you could try is boot with the HDMI video. Then in display preference, select 'Detect Displays' by holding down the Windows Key, the option will appear. You internal LCD should come up then. See if the LCD is set as the default, if not, then set it. I can't guarantee the LCD will come up on a reboot without the HDMI display. I'll need to go back and check to see what changed. The original DSDT was working perfectly before for NVS, just have to figure out why it's no longer working without changing anything. I'll keep everyone posted. By the way, did you make sure that 'Skip Nvidia GFX' is not check in org.chameleon.boot.plist?