Should I bother with SSDT?

[aFlockOfMoosen]

My rig is working fine for what I need it for, but would i see a substantial improvement if i installed the core i7 SSDT from MB? I don't think over clocking is necessary for me at this time. I'm also curious if installing the SSDT is something I can do now, with an already operation setup, or something that needs to be done from a fresh install. I honestly don't even know what it stands for... I'm waiting for one of those cute little animated PSAs

On a sidenote, i've also been using the 3, 1 Mac Pro system definition... I'm tempted to install a newer one from MB, but I've no idea the ramifications

 

[nukedukem]

The reason SSDT's have come to light is because the new update 10.7.4 changed the power management of sandy bridge processors. What this means is that if you are running a sandy bridge system and you upgraded to 10.7.4, your CPU may not scale it's frequency properly. This happens for anyone regardless of whether or not they overclock the CPU.

Normally a processor will change frequency depending on the load you are putting on your system. This can reduce the power needed by your computer (reduce your electricity bill) by dropping your 3.4 GHz CPU down to 1.6 GHz, for example, if you aren't doing much on your computer.

What an SSDT will do is tell OSX what frequencies to scale your CPU in order to give you power when you need it and reduce it when you don't. The update seems to prevent sandy bridge processors from going higher than the lowest frequency (in the example I used, the CPU won't go higher than 1.6 GHz).

There are several ways to determine if your CPU is properly scaling frequencies. Just search the forum for how to use MSRDumper, HWMonitor, or geekbench.

If you determine that your CPU is affected by this update, you can create an SSDT for your system without the need to do a fresh install. Your current system definition is probably just fine. If it's not broke don't fix it! Just follow the guides around here to "install" an SSDT. I hope that helps a little.

 

[aFlockOfMoosen]

The reason SSDT's have come to light is because the new update 10.7.4 changed the power management of sandy bridge processors. What this means is that if you are running a sandy bridge system and you upgraded to 10.7.4, your CPU may not scale it's frequency properly. This happens for anyone regardless of whether or not they overclock the CPU.

Normally a processor will change frequency depending on the load you are putting on your system. This can reduce the power needed by your computer (reduce your electricity bill) by dropping your 3.4 GHz CPU down to 1.6 GHz, for example, if you aren't doing much on your computer.

What an SSDT will do is tell OSX what frequencies to scale your CPU in order to give you power when you need it and reduce it when you don't. The update seems to prevent sandy bridge processors from going higher than the lowest frequency (in the example I used, the CPU won't go higher than 1.6 GHz).

There are several ways to determine if your CPU is properly scaling frequencies. Just search the forum for how to use MSRDumper, HWMonitor, or geekbench.

If you determine that your CPU is affected by this update, you can create an SSDT for your system without the need to do a fresh install. Your current system definition is probably just fine. If it's not broke don't fix it! Just follow the guides around here to "install" an SSDT. I hope that helps a little.

Thanks for the info! Would I know if i was running a Sandy Bridge system? How exactly can I tell? I didn't do anything Sandy Bridge specific to my knowledge during the build, but I am having a graphics lag since the update.

 

[Stork]

According to your system description in your signature block, you are NOT running a Sandy Bridge system. I, too, have a P55 systems and don't need the SSDT mod.

BTW, Sandy Bridge is the 2nd generation Intell Core i3/i5/i7 processors that have a dash 4 digit number in the 2000 number range.

 

[ConteMario]

According to your system description in your signature block, you are NOT running a Sandy Bridge system. I, too, have a P55 systems and don't need the SSDT mod.

BTW, Sandy Bridge is the 2nd generation Intell Core i3/i5/i7 processors that have a dash 4 digit number in the 2000 number range.

SO Stork you use the SSDT only for sandy bridge and you are not using (e.g.) for a second graphic card?

 

[Stork]

I never need a SSDT for my 5-system motherboard systems. However, I use the the appropriate Sandy Bridge SSDT for my SB processors from MultiBeast. No problems with them, and they're working great since day one. Sandy Bridge i5 and i7 and the i5 and i7 "K" processors need the SSDT for proper system performance. See the MultiBeast v9.2.0 Features document, which comes with MultiBeast, page 8.

Additionally, all my systems since Sandy Bridge (6-series motherboards and 2000 series i5/i7 processors) use a power management SSDT which I generated from PikeRAlpha's script. For newer systems, toledo has created a SSDT for power management that's drag and drop for Skylake and newer processors.

I don't use multiple graphics cards in my systems, only one in each, which is sufficient to drive two monitors.