DSDT for chipset z77/h77

Hello guys,

I want to get a motherboard mini-itx with one of these chipsets.
Sorry about my lack of knowledge about it, but I don't understand why there is no DSDT for this chipsets...
And another thing, what is the meaning of MSR? And what is the importance to be locked? And there is anyway to bypass it? And why just Gigabyte has it unlocked?

I wanted to get clarify of that since long time ago.

Thanks you very much, and sorry for the inconveniences.

ed_co said:

Hello guys,

I want to get a motherboard mini-itx with one of these chipsets.
Sorry about my lack of knowledge about it, but I don't understand why there is no DSDT for this chipsets...
And another thing, what is the meaning of MSR? And what is the importance to be locked? And there is anyway to bypass it? And why just Gigabyte has it unlocked?

I wanted to get clarify of that since long time ago.

Thanks you very much, and sorry for the inconveniences.

Click to expand...

Searching the forum you'll find DSDTs for many boards with series 7 chipsets. I also patched some of them myself, including one for an mini-ITX board from Asrock, and as many manufactures like ASUS, Asrock, Gigabyte and MSI are using an AMI BIOS for those boards the patches needed are almost the same.

MSR is an abbreviation for Machine Specific Register which are used by the BIOS / OS to configure certain CPU features. Especially MSR 0x2e is of great importance for OS X as it is involved in the setup of CPU power management. Bit 15 of this registers is a lock bit. Once it is set the CPU refuses attempts to write to the register causing a general protection fault, which results in a kernel panic under OS X when AppleIntelCPUPowerManagement.kext tries to write to the register. The BIOS on most boards sets the lock bit after configuring the CPU so that the OS can't modify the cofiguration. Currently only mainboards from Gigabyte are not affected. Other boards need a workaround like a patched version of AppleIntelCPUPowerManagement.kext or a modded BIOS in order to get working speedstep/sleep.

Mieze

Hey Mieze,

Thanks for the explanation. It was really useful.
There is any reason for the manufacturers to lock that bit?
Why doesn't gigabyte care about it?
What was the chipset generation who started with that lock, z68?

Are you spanish Mieze?, I am telling you because of your signature. I am spanish.

Cheers,

E.

ed_co said:

There is any reason for the manufacturers to lock that bit?

Click to expand...

Yes, it prevents changes to the selected configuration by the OS so that the settings stay intact until the machine is rebooted.

ed_co said:

Why doesn't gigabyte care about it?

Click to expand...

Maybe they have found a market niche? Linux is also affected by that issue so there might be demand for systems with unlocked MSR.

ed_co said:

What was the chipset generation who started with that lock, z68?

Click to expand...

The MSRs reside inside the CPU itself, they aren't part of the chipset. As I'm relatively new in the hackintosh community I have little experience with pre-Sandybridge architectures so that I don't know when Intel introduced that feature.

ed_co said:

Are you spanish Mieze?, I am telling you because of your signature. I am spanish.

Click to expand...

Lamentablemente no, soy alemana pero aprendí castellano en la universidad. Vivo en un pueblo en el oeste de Alemania muy cerca de la frontera neerlandés.

Mieze

Thanks for the quick reply.

Just another quick question. What is the advantage not having DSDT? I think that is all advantages, if you can have all in the DSDT, less files you need to patch, ergo more vanilla. Right?

Your spanish is brilliant. Really nice level. Sólo un pequeño error, frontera es femenino, luego es "neerlandesa" no "neerlandes", incluso mejor decir "holandesa", ya que es mas habitual. Lo demás está perfecto.

Enhorabuena!!

ed_co said:

Thanks for the quick reply.

Just another quick question. What is the advantage not having DSDT? I think that is all advantages, if you can have all in the DSDT, less files you need to patch, ergo more vanilla. Right?

Click to expand...

Although you can run your machine without a DSDT, in most cases you'll need it in order to get a fully functional system.

Mieze