My Dell Precision M3800 is playing peekaboo with me.

[the-darkvoid]

Change DVMT pre-allocated to 128MB, do NOT change any other settings.
(Most of the settings are only available because you unlocked the BIOS and changing them can brick your laptop)

Next apply a Clover framebuffer patch to change your framebuffer stolen memory size to 128MB.
For 10.10.2 I am using framebuffer 0x0a260006.

 

[DJWackMac]

So I tried your framebuffer patches, plus 96:44:44, and 96:46:46, but the issue still isn't fixed. I made a script to generate these patches, it's attached to this post. I also went into the BIOS and turned off some of the settings related to both the IGPU and LCD power management, but they didn't fix the issue so i turned them back to what they were.

EDIT: I posted this before I read the-darkvoid's reply, I'll try those suggestions now.

 

[DJWackMac]

I changed the DVMT pre-allocated memory to 128M, used my script to generate a patch for 128:34:34, ensued that my ig-platform-id is 0x0a260006, and I get a Kernel Panic on early boot "Machine Check Exception: <some address> ..."

 

[RehabMan]

I changed the DVMT pre-allocated memory to 128M, used my script to generate a patch for 128:34:34, ensued that my ig-platform-id is 0x0a260006, and I get a Kernel Panic on early boot "Machine Check Exception: <some address> ..."

Show us the patch you used.

 

[DJWackMac]

Show us the patch you used.

My generator script spits out the following for 128:34:34:

[FONT=Menlo]KextsToPatch String: "0600 260A 0103 0303 0000 0008 0000 2002 0000 2002"[/FONT]
[FONT=Menlo]-----OR-----[/FONT]
[FONT=Menlo]KextsToPatch Data:   "BgAmCgEDAwMAAAAIAAAgAgAAIAI="[/FONT]

So I enter it into my config.plist like so:

<dict>
				<key>Comment</key>
				<string>Enable 128MB BIOS, 34MB Framebuffer, 34MB Cursor for Azul framebuffer 0x0a260006</string>
				<key>Find</key>
				<data>
				BgAmCgEDAwMAAAACAAAwAQAAYAA=
				</data>
				<key>Name</key>
				<string>AppleIntelFramebufferAzul</string>
				<key>Replace</key>
				<data>
				BgAmCgEDAwMAAAAIAAAgAgAAIAI=
				</data>
			</dict>

Then I change the DVMT Pre-Allocated to 128MB and reboot, and then Machine Check Exception. The backtrace says its in AppleACPIPlatform, don't know if that's useful information or not.

 

[RehabMan]

...
Then I change the DVMT Pre-Allocated to 128MB and reboot, and then Machine Check Exception. The backtrace says its in AppleACPIPlatform, don't know if that's useful information or not.

After changing these options, did you re-extract/re-patch DSDT/SSDTs?

It is a requirement.

SystemMemory addresses can/will change with major changes to BIOS options, BIOS upgrades, or changes to hardware configuration (eg. changing RAM installed, changing other hardware).

 

[DJWackMac]

I did not repatch the DSDT/SSDTs. I repatched and it got rid of the kernel panic, and in addition I performed the following steps:

1. Booted without kernel cache
2. Used Kext Wizard to regenerate cache
3. Rebooted normally

...but the issue still persists.

 

[RehabMan]

I did not repatch the DSDT/SSDTs. I repatched and it got rid of the kernel panic, and in addition I performed the following steps:

1. Booted without kernel cache
2. Used Kext Wizard to regenerate cache
3. Rebooted normally

...but the issue still persists.

Change something in your config.plist that you can see evidence of.... just as a way to verify you're booting with the configuration you think you are. You could also look in your Clover bootlog for confirmation that the patches are being applied. Also, double check that the patch is finding a match against the kext you have installed (use a hex editor to look for the Find data).

 

[DJWackMac]

Okay, so I've now done the following as well:

• Checked the Clover bootlog for confirmation of patch
• Checked AppleIntelFramebufferAzul for the find bytes
• Copied EDID from Windows and injected it with Clover

I also discovered that if I go into System Preferences and change the display settings from "Default for display" to "Scaled" and then change the scaling to any mode below the highest (which is 1920x1080 on my machine), the graphics function normally. I would like to be able to select the 1920x1080 scaling mode though without problems.

 

[RehabMan]

...
I also discovered that if I go into System Preferences and change the display settings from "Default for display" to "Scaled" and then change the scaling to any mode below the highest (which is 1920x1080 on my machine), the graphics function normally. I would like to be able to select the 1920x1080 scaling mode though without problems.

So, you're doing this from an external monitor? Because it would seem rather difficult change the settings when the display is black, no?

I wonder if creating a custom plist for your display would help... See here: http://www.tonymacx86.com/mavericks-laptop-support/133254-adding-using-hidpi-custom-resolutions.html