Turbo Boost technology/Intel technology/Mobiles technologies/Softwares Technology

Intel promotes the Turbo Boost technology in its new Core i7 Mobile processors as a way to adapt to the needs of the software and get more performance from the chip, but this isn't the real reason the technology exis
It's easy to see how this works when just one or two cores are being actively used; whatever power the other two or three cores would have consumed can be redirected over to the active cores, allowing them to run at higher speeds.
The quad-core mode of Turbo Boost is a little more subtle; it works when the four cores aren't running a worst-case workload--for example, integer-heavy processing, since it's generally floating-point calculations that consume the most power--so they aren't bumping into the TDP limit. Turbo Boost can increase the frequency of all four cores until they're running as fast as they can for the current workload.
Eden said that the Turbo Boost controller samples the current power consumption and chip temperature 200 times per second and makes whatever adjustments are necessary. Of course, if Windows isn't asking for more performance, Turbo Boost doesn't deliver it.
In the ideal case, where just one core is running, Turbo Boost can increase the clock rate on that core from the chip's rated speed of 2GHz to 3.2GHz--that's like getting a chip eight speed grades faster than what you paid for. (Speed grades, or "bins" in the parlance of semiconductor manufacturing, usually go up in steps of around 10 percent to 20 percent. The Core 2 Mobile processor P series parts have speeds of 2.26, 2.4, 2.53, 2.66, and 2.8GHz. The T series extends this range to 2.93 and 3.06GHz, so by this measurement, 3.2GHz would be about eight steps above 2GHz.)
That's how Intel wants everyone to think of Turbo Boost, but it isn't really the natural way. To explain why, I'll have to digress briefly and describe how chips are designed and built.
Any given microprocessor core architecture, like the Nehalem architecture underlying these new parts, has a certain typical complexity expressed in terms of a number of equivalent gate delays. The clock period has to be long enough to accommodate all of these gate delays.
Any given process technology, like Intel's 45nm "P1266" technology, has its own characteristics. These can be tweaked somewhat to optimize for higher speed, higher yield, lower power consumption, higher transistor density, etc., but generally a company like Intel has just one recipe for high-performance microprocessors like the Core i7.
The combination of the gate delays in the logical design of a chip with the physical transistor and interconnect performance figures for a process determines a maximum clock speed for that chip on that process. As chips are manufactured, they're tested for functionality and speed against various standards like power consumption and temperature rating; each speed grade ends up with its own part number, like "920XM" for the fastest Core i7 Mobile chips.
For the Core i7-920XM, that maximum speed bin is 3.2GHz, not the 2GHz value which is marked on the part. In principle, the 920XM could run all of its cores at 3.2GHz all the time if enough power was available and if the heat sink could keep the chip cool. (This is why Turbo Boost isn't like consumer overclocking: the chip is operating within its design specifications at all times.)
In a laptop, the potential for quad-core 3.2GHz operation just can't be realized. Intel selected the 55W TDP specification for the 920XM because that's a practical limit for a laptop processor. Combine that number with the rest of the chipset, the memory, a high-end graphics chip, and a big high-resolution LCD panel, and the whole laptop might be consuming 80W-100W when running all-out.
the 920XM were configured to run all of its cores at 3.2GHz, I estimate it would consume at least 110W of power for the CPU alone--completely untenable in a mainstream laptop. (Though it's true that some original equipment manufacturers make laptops using desktop Nehalem processors; they're just huge, heavy, and hot.)
o Intel calculated how much it has to slow down the 920XM in order to meet the industry-standard definition of TDP, which amounts to a worst-case real-world workload running on all four cores. (Maximum power is defined in terms of a worst-case synthetic "power virus," but since real applications aren't that brutal in their processing demands, maximum power is only of interest to chip and system designers.)
For the 920XM, that slowdown worked out to 2GHz, and that's why the chip is rated at that speed.
It's worth looking at the previous Extreme Edition mobile processor, the Core 2 Extreme QX9300, which is a quad-core chip that can run all four cores continuously at 2.53 GHz. In spite of the QX9300's faster clock speed, there will still be many situations where the 920XM is faster on quad-core workloads because of the newer Nehalem microarchitecture, which usually gets more work done per clock period.
I haven't seen any good benchmarking comparisons between these two chips. Intel published some selected benchmarks at IDF, but not many, and it isn't clear to me what aspects of chip performance were being stressed.
But for dual-core and single-core performance, the 920XM should be much faster than its predecessor, combining the superior Nehalem architecture with the higher clock speeds enabled by Turbo Boost. The QX9300 has a simpler feature called Dynamic Acceleration Technology, but its effect is limited to only about one speed grade, roughly 10 percent. In most dual-core cases, and I think in all single-core cases, the 920XM will be much faster for the same power consumption.


The new "Clarksfield" Core i7 Mobile processors introduced at the Intel Developer Forum last week are certainly very impressive. They're huge high-performance quad-core chips with Hyper-Threading, support for two channels of DDR3-1333 DRAM, and an on-die PCI Express controller for the fastest possible connection to discrete graphics chips.
The maximum frequency of Intel® Turbo Boost Technology is dependent on the number of active cores. The amount of time the processor spends in the Intel Turbo Boost Technology state depends on the workload and operating environment, providing the performance you need, when and where you need it.
When the processor is operating below these limits and the user's workload demands additional performance, the processor frequency will dynamically increase by 133 MHz on short and regular intervals until the upper limit is met or the maximum possible upside for the number of active cores is reached. Conversely, when any of the limits are reached or exceeded, the processor frequency will automatically decrease by 133 MHz until the processor is again operating within its limits.