How to see if turbo boost is working on I7 860 CPU?

Question

I just build myself a new system with a Intel I7 860 CPU. When loading it using a single threaded application like Super PI, CPU-Z shows 2.933Ghz as speed. Now I understood that the I7 goes into turbo boost mode up to 3.46GHz for a single core.

How can I check that? Is there a utility to monitor CPU speed per core?

Solution 1

Assuming turbo mode is activated in the BIOS and that you are using a Windows OS, Argus Monitor should tell you when turbo mode is being used.

Solution 2

CPU-Z should show the extra speed when the turbo mode is activated.

Comments

[Jan Derk]

That is an excellent utility showing the CPU speed and multipliers for all cores. The turbo mode is working fine.

[Nathan Fellman]

all cores should have the same frequency

[UNK]

@Nathan; No, that's what turbo boost does, overclocks specific, in-use cores.

[Nathan Fellman]

No it doesn't. Look here: intel.com/support/processors/sb/cs-029908.htm where it says: Is turbo frequency the same for all active cores in the processor? Yes

[100rabh]

@Nathan - What the literature & Phoshi says is that Turbo boost can and will shut down cores which are not in use and apply a spefic frequency boost, across all the cores - ie, if turbo boost is applied on a Quad core with 2 cores being in active, the 2 active cores will get an increase in the same frequency

[100rabh]

@Nathan: The keyword is active cores, not just cores

[Nathan Fellman]

The inactive cores don't have a clock. Talking about frequency with regard to them is meaningless. Even so, when their clocks turn on on the way to becoming active, they will have the same frequency as the others, even if they aren't technically active yet.

[100rabh]

Intel's illustration says otherwise youtube.com/watch?v=llOXMPXH2VA

[Gnoupi]

"If I'm watching an orange by complete darkness, its visible color is black."

[coneslayer]

@Nathan There's only one BCLK, but a core operates at the BCLK times a multiplier, and each core has its own multiplier. It's the multiplier that's manipulated by Turbo Boost and SpeedStep. On my i7-930, the BCLK is 133 MHz, with a "standard" multiplier of 21 for 2.8 GHz. Tools like TMonitor will show three lightly-loaded cores running at a multiplier of 12 (power conserving) at the same time that another core is running at 22-23x (Turbo Boost, 2.92-3.06 GHz).

[coneslayer]

See my comment above. Each core has its own multiplier, which can and does differ from core to core at any moment in time. I believe the meaning of the statement you quote is that no core is special: On an i7-930, all cores have the same turbo frequency of 3.06 GHz. That doesn't mean that they all run at the same frequency all the time. See screenshots at cpuid.com/softwares/tmonitor.html

[TyCy]

@Gnoupi: actually Matt ain't far off: I'm pretty sure I read an Intel paper where they stated that these newer Core i7 have the ability to entirely shut down unused cores, making them effectively draw zero power (I mean, the article was precisely boasting the fact that unused cores wheren't drawing any power at all). I think in that case it isn't far fetched to say they're at "zero Mhz". Btw your snarky quote is a bit snarky coming from a mod ;)

[Gnoupi]

@weezy - to be fair, I wasn't a mod then, just a regular user.