Speedstep: DSDT edit vs. Enabled by imac 11,1 smbios, OC?

[cakemonster]

I have seen several references to the fact that for the chips actually in the imac (i5 750 and i7 860) that the imac smbios enables speedstep without DSDT edits...

1. Question 1

I find that for best results for both Geekbench and everyday performance (OC or not) do not include any SS info in your DSDT. The i7 860 and P55 run SS and Turbo natively if your system uses iMac 11,1 (on other forums most argue in favour of NO DSDT SS info), therefore no need to include anything in your DSDT. I am not sure however if you can still OC without adding anything to the DSDT and still get SS and Turbo.

First, are folks finding the that DSDT edit is not necessary in general to get speedstep if using the imac 11,1 smbios?

Question 2:

I have read numerous places that you have to be careful with speedstep and turboboost with OC, others say it is OK if you keep it a mild OC. Turbo seems to be the main contributor as when it jumps it may not be stable at that clock speed from an initially stable OC. As such knowing if it is on or off is helpful. As I understand it you can still turn it off in Bios with the Imac 11,1 smbios?

Edit: Looks like this thread has gone toward answering this question, but folks are still figuring it out...

viewtopic.php?f=7&t=862

 

[adamsmasher]

I have the iMac smbios and I have speedstep enabled without the edits to my DSDT (I do have all the CPU options enabled in BIOS, although I have done no overclocking). Unless you're looking at overclocking your CPU a lot it really shouldn't be an issue.

 

[treuben]

Does anyone know if Imac 11, 1 enables speedstep (and or turbo) on i5 2500 or 2500K? Also - Is imac 11, 1 the only sys def that does this that we know? eg Will Mac Pro 5, 1 do such things?