What is the real Turbo Boost for i7-4930K ?

[Edgemeal]

If you look at the i7 Turbo Boost Table the i7-4930K Bin Upside and Turbo MHz don't add up!

I'm guessing the Turbo MHz part is correct but the Bin Upside row are off by +1?
Can some one please clarify.
Thanks!

 

[Dave3000]

I own an i7-4930k. When I set the CPU multiplier to Auto and leave the c-state settings on Auto, 5-6 loaded cores turbo to 3.6Ghz, 2-4 loaded cores turbo to 3.7Ghz, and when only 1 core is loaded it turbos to 3.9Ghz. This is on an Asus P9X79 Pro motherboard.

 

[blackened23]

Also, you can simply enable "multi core enhancement" in the BIOS which will turbo all cores to either 3.9ghz or whatever your overclocked speed is.

Generally speaking, when you overclock, all cores turbo to your specified speed and do not behave according to the auto settings turbo boost. Or if you want the same turbo on all cores, simply select multi core enhancement as mentioned in your motherboard BIOS.

I'm not sure if the P9X79 pro has this feature, but most asus motherboards with the latest BIOS revisions support it. I use it on the Z87 Pro. Same concept, but for a 4770k.

 

[toyota]

Also, you can simply enable "multi core enhancement" in the BIOS which will turbo all cores to either 3.9ghz or whatever your overclocked speed is.

Generally speaking, when you overclock, all cores turbo to your specified speed and do not behave according to the auto settings turbo boost. Or if you want the same turbo on all cores, simply select multi core enhancement as mentioned in your motherboard BIOS.

I'm not sure if the P9X79 pro has this feature, but most asus motherboards with the latest BIOS revisions support it. I use it on the Z87 Pro. Same concept, but for a 4770k.

you dont use multi core enhancement when overclocking. you simply choose to apply whatever speed you have chosen for all cores aka "Sync All Cores". multi core enhancement setting will have no impact anyway once you have done that. multi core enhancement is really only for those that dont want to do real manual oc but still get the full single core turbo speed applied to all 4 cores while touching no other settings.

 

[bradly1101]

Also, you can simply enable "multi core enhancement" in the BIOS which will turbo all cores to either 3.9ghz or whatever your overclocked speed is.

Generally speaking, when you overclock, all cores turbo to your specified speed and do not behave according to the auto settings turbo boost. Or if you want the same turbo on all cores, simply select multi core enhancement as mentioned in your motherboard BIOS.

I'm not sure if the P9X79 pro has this feature, but most asus motherboards with the latest BIOS revisions support it. I use it on the Z87 Pro. Same concept, but for a 4770k.

My GA X79-UP4 doesn't have that feature, but you can turn off turbo boost or adjust turbo freq. It looks like this in my BIOS:

What's strange to me though is that with the default settings above, CPUZ says my 4930K is running at 3.9Ghz with all six cores presumably loaded in the Cinebench 15 benchmark. RealTemp shows the same:

 

[Edgemeal]

Also, you can simply enable "multi core enhancement" in the BIOS

Forget all that, I'm asking about Intel's turbo spec table.
Either I don't understand it or the number of bins are a typo.
Look at the i7-4930K table again, and answer me this,..
(1C) How can 3.4 +6 bins = 3.9? (wouldn't that be 4.0?)
(6C) How can 3.4 +3 bins = 3.6? (wouldn't that be 3.7?)

 

[Edgemeal]

My GA X79-UP4 doesn't have that feature, but you can turn off turbo boost or adjust turbo freq. It looks like this in my BIOS:

Well at least that coincides with Intel's MHz table, I guess their number of Bins are just typos.

Not sure about CPU-Z, ( you have multi-core enhancement enabled?).

 

[unclewebb]

It looks like the spec table was put together by someone that is a little mathematically challenged.

With CPU-Z, click on the About tab and then push the Save Report(.TXT) button. In your report, have a look for this line.

MSR 0x000001AD		0x00000000	0x22222324

The MSR 0x1AD register tells you what maximum turbo multipliers your CPU has access to depending on how many cores are in the active state. The above info is from my Core i7-4700MQ that has been overclocked +2 bins. The data is in groups of 2 digits and the numbers are in hexadecimal format.

0x22 = 34 - 4 cores active
0x22 = 34 - 3 cores active
0x23 = 35 - 2 cores active
0x24 = 36 - 1 core active

If these are set all the same then your CPU will use the same maximum turbo multiplier no matter how many cores are active. After booting up, have a look at this register and you can see what values your bios has decided to set your CPU to. Some bios options might be hard to understand.

The 6 core CPUs will have 4 more digits of information in the left side of register 0x1AD which contains information for the 5 and 6 active core multipliers. Subtract these numbers from the default 34 multiplier and you can send an updated table to Intel so they can fix their docs.

 

[Edgemeal]

It looks like the spec table was put together by someone that is a little mathematically challenged.

With CPU-Z, click on the About tab and then push the Save Report(.TXT) button.

OK thanks, sent mathematically challenged Intel some feedback. :biggrin:

CPU-Z also seems to show the same info (in plain english?) under "Processor #", (just before "Thread dumps").

Note: i7-3770 at stock,

Turbo Mode		supported, enabled
Max non-turbo ratio	34x
Max turbo ratio		39x
Max efficiency ratio	16x
Min Power		60 Watts
O/C bins		+4
Ratio 1 core		39x
Ratio 2 cores		39x
Ratio 3 cores		38x
Ratio 4 cores		37x

 

[Rakehellion]

If you're overclocking, disable turbo.

 

[unclewebb]

	O/C bins		+2
	Ratio 1 core		36x
	Ratio 2 cores		35x
	Ratio 3 cores		34x
	Ratio 4 cores		34x

That is the CPU-Z in plain English version of MSR 0x1AD. There is another hidden register that can over ride this register so it is possible that this information is not accurate. My 4700MQ will report the same thing above whether I am using the +2 bins of overclocking or not.

If you're overclocking, disable turbo.

Some motherboards might give you an option in the bios to disable Turbo Boost but those options are misleading. The default multiplier for a Core i7-4930K is 34. To use any multiplier higher than this, Turbo Boost must be enabled within the processor. If the bios lets you turn this off, when you boot up, if it sees you want to use a multiplier higher than 34, it automatically turns Turbo Boost back on. It has to or else your CPU will be stuck at 34.