Bios Mods -The Best BIOS Update and Modification Source

Okay, I just tried random values with SFUN (sounds like fun!).
Results for the SFUN variable in A04 SSDT:
0x00, 0x08 - breaks Catalyst Control Center, AMD card becomes unusable
0x01 - app-based switching only (like in A04)
0x02 - manual switching mode only - like in PX3.0 laptops
0x03 - app-based only (original value in A04)
0x04, 0x07 - black screen after OS startup

Same variable in A11 SSDT:
0 - breaks Catalyst Control Center, AMD card becomes unusable
1 - both switching methods are available (default)
2 - same as 0

I also tried replacing _SB_PCI0PEG0PEGP_OFF with _SB_PCI0PEG0PEGP_ON_ in the same SSDT table, and it broke the Intel GPU part. The screen would turn black after switching between cards.

I think it's obvious that forcing AMD card to take over is only possible with some heavy DSDT editing (and there's no guarantee it would work).

We need to find a proper way to fix DSDT and make it work with the capsule

I'm just baffled that phoenixtool won't reintegrate it properly, considering it was coded with such an option with mind .. I'm actually looking into disabling ST Micro Accelerometer and thus DSDT modification wouldn't hurt.

Hmm, I don't really think there's a problem with reintegration. I basically hex edited the existing tables and reintegrated them using the same PhoenixTool, and it worked fine.
I also don't think it's related to the size of the file: SSDTs in A04 and A11 are different in size (only 1 byte though).
I made some random changes to 76AED82E-77DE-42CA-8C27-E9D71DF606C7_0_665.ROM (SSDT AmdTabl) while preserving its original size, and it didn't start flashing... However, it worked fine with 1-byte alterations and fixed checksum.
Maybe it tries to actually read and interpret the compiled code at some point?

DSDT is always interpreted...never executed, the methods in it are though , but I assume there should be only a basic integrity check for crc, nothing really advanced, because lets face it, verifying every byte would take a descent amount of time.

It's a PhoenixTool bug after all... I tried A04 DSDT and it didn't flash either. I then tried to merge back the original A13 DSDT and it didn't work. So yeah, you're right, PhoenixTool fails to reintegrate it properly for some reason...

EDIT: Hmm, I got it to reintegrate. I opened F33E.... .mod, clicked Structure, then extracted 7E374E25-8E01-4FEE-87F2-390C23C606CD. It created a .MOD file which I hex edited. I then clicked Structure again and replaced 7E374E25-8E01-4FEE-87F2-390C23C606CD with the modified one. It reintegrated properly and I was able to flash it.
Now we have to figure out how to combine modified tables into one module. Shouldn't be too difficult because it seems to be just all tables slipped together with some padding data around them.

Edit: Almost figured out how these MODs are composed, will update soon.

Cool, keep posted.

IT WORKED!!!

I looked at the structure of the MOD files and found the problem. PhoenixTool seems to add some garbage at the end of the file. Try doing this to get your modified DSDT to work:

1. Reintegrate DSDT the usual way (Set manufacturer to Dell, replace the file in the DUMP folder, etc.)
2. Open the updated module (F33E..._SLIC.MOD), press Structure and extract 7E374E25-8E01-4FEE-87F2-390C23C606CD.
3. Open the extracted file in a HEX editor and delete the last byte of the file if it is hex FF.
4. At offset 0x14, write the correct size of the module (in hex) after modification. For example, if your module is 44287 (ACFF in hex) bytes, write FF AC like this: http://imgur.com/BIU1ui3 . Don't forget to save it!
5. In PhoenixTool, click Structure again and replace 7E374E25-8E01-4FEE-87F2-390C23C606CD with the one you hex edited.
6. Open BIOS1.WPH and replace the F33E.... module.
7. Flash it!

By the way TW, if you currently have any modified DSDT on your Hackintosh, I'm willing to test it now just to confirm that this method works.

EDIT: Updated the instructions.

Woah, good job!
I have a heavily altered DSDT with Windows stuff removed, so it wouldn't work as is. I can edit it quickly though to fix the freezing bug for Fn+F2 in UEFI Boot mode. Also the part that Dell screwed up, the one I showed earlier, post #91 in this thread. Which BIOS are you currently running, A13?
[attachment=5001]

Yeah, I'm on A13 right now. I can't test the Fn+F2 fix though because my Windows is not an UEFI installation.

A few ideas I'd really love to try out with DSDT modding:

1. Disable ST Micro Accelerometer
2. Prevent Intel Management Engine Interface device from showing up in Device Manager
3. Fix Fn+F3 issue with the touchpad?
4. Switchable Graphics... You know it brought me here in the first place

1. Possible
2. Not possible
3. Not possible as this is handled by driver, one can alter touchpad ID though to be version 05 instead of 04
4. Sorry, I have Intel-only model :|

Updated my post with a slightly edited A13 DSDT, fixed Dell's ACPI mistake and removed FOWM call, lets see if it breakes Fn+F2 in Legacy Boot mode..