i7 Core 920 and Multiplier

[toddd240]

I have been fiddling with my new 920 and when using Vista I set the power settings to heavy performance. This locks the CPU at its highest setting and doesn't allow for cpu throttling. In Cpuz, with heavy performance setting on high, the multiplier shows 21 and with my BCLK set to 150 shows 3150. I thought the multiplier was locked at 20 on this processor.

Anybody have any ideas?

 

[burebista]

You see Turbo in action with 21 multiplier. I think.

 

[toddd240]

You see Turbo in action with 21 multiplier. I think.

Thats what I suspected. So theoretically by cranking up Windows to heavy performance will give you a permanent 21 multiplier for the 920.

 

[rdrash]

That is Intel Turbo Mode kicking in....it only affects single threaded apps because only 1 core is actually being raised to that speed.

Below is a great explanation (I ripped this from XS) written by Sayaa from Foxconn....

The return of the Turbo-Button?
The max turbo multipliers are stored in seperate registers from the "normal" max allowed cpu multipliers, and they can not be changed (unless you hack the cpu ) The turbo multipliers can not be forced to stay on all the time... at least not directly... you can fool the cpu into believing all the conditions that are necessary to run turbo mode are there, even if they are not 
the highest boot multiplier is the highest "normal" multiplier...

for the i7-965 it works like this:

IF turbo is disabled
OR vcore is unstable
OR current is too high
OR Tdp is too high:

4 cores will run at 24x133=3200Mhz
3 cores will run at 24x133=3200Mhz
2 cores will run at 24x133=3200Mhz
1 cores will run at 24x133=3200Mhz

IF Turbo is enabled
AND vcore is stable 
AND current is ok 
AND the TDP is below the limit

4 cores will run at 25x133=3450Mhz
3 cores will run at 25x133=3450Mhz
2 cores will run at 25x133=3450Mhz
1 core will run at 26x133=3600Mhz


for the i7-940 it works like this:

IF turbo is disabled
OR vcore is unstable
OR current is too high
OR Tdp is too high:

4 cores will run at 22x133=2933Mhz
3 cores will run at 22x133=2933Mhz
2 cores will run at 22x133=2933Mhz
1 cores will run at 22x133=2933Mhz

IF Turbo is enabled
AND vcore is stable 
AND current is ok 
AND the TDP is below the limit

4 cores will run at 22x133=2933Mhz
3 cores will run at 22x133=2933Mhz
2 cores will run at 22x133=2933Mhz
1 core will run at 23x133=3050Mhz

so you see, turbo is really not that useful for most of the cpus, its only useful for the 965, where it basically auto overclocks the cpu... so basically the Core i7 lineup looks like this:

920 2800Mhz BUT if vcore is unstable, current is too high, or temps are too high, it will run slower.
940 3050Mhz BUT if vcore is unstable, current is too high, or temps are too high, it will run slower.
965 3600Mhz BUT if vcore is unstable, current is too high, or temps are too high, it will run slower.

What turbo really is, is a more advanced form of throttling the cpus from those clockspeeds down to a SAFE speed that will work even with high temps, fluctuating vcore and high current. instead of advertising a 3600mhz cpu that throtles down to 3400 or less depending on the situation, which would cause a lot of complains, the cpus are rated at 3200mhz and everything else above it is a BONUS, so nobody can complain

 

[STi]

On the 965 once you change multiplier turbo and speed stepping is disabled ..Atleast on the p6t bios.

Do all the x58 boards do this? I actually wouldn't mind both features ..i'm stuck on having to use all this wattage full time for 4.2Ghz.