Intel Core i7-680UM vs Intel Core i7-640M
Intel Core i7-680UM► remove
The Intel Core i7-680UM is a Ultra Low Voltage dual-core processor for small and light laptops. It is clocked with 1.47 - 2.5 GHz (if Turbo Boost is enabled). The 680UM is the fastest ULV CPU in Q4 2010. Each core is based on the Nehalem (Westmere) micro-architecture. Hyperthreading enables the Dual Core CPU to handle 4 threads at once (for a better usage of the pipeline). Compared to the Core i7-640M and the i7 640LM CPUs, the 680UM is much slower (due to the lower clock rate) but more power efficient.
A feature of the new Core i7-680UM is the integrated graphics card (called Intel HD Graphics) and memory controller. Both are on a separate die that is still manufactured in 45nm whereas the CPU die is already manufactured in the new 32nm process.
Due to the integrated memory controller, the HyperThreading and Turbo Boost, the Core i7-680UM is faster than a similar clocked Core 2 Duo (1.4 GHz) in all (us known) applications and benchmarks. Still the Turbo Boost may not trigger very often (sometimes it is even not activated in the BIOS) and therefore the maximum of 2.53 GHz could not be important. If the Turbo triggers, the CPU may be as fast, as a 2.6 GHz Core 2 Duo in single threaded applications.
The 32nm cpu cores of the Westmere generation can also process some new instructions to accelerate AES encryptions. Modern applications that support AES encoding can profit significantly using the new instructions (e.g. the Communications Suite test in the PCMark Vantage boosts up to 70% using AES in the faster Core i5-520M).
The integrated Intel Graphics Media Accelerator HD (GMA HD) graphics card is between 166-500 MHz (Turbo Boost) and therefore the base speed is clearly below the non low voltage versions. The performance should still be faster than the old GMA 4500MHD.
Intel Core i7-640M► remove
The Intel Core i7-640M is a high end dual core CPU for laptops and clocks (due to the Turbo Mode) from 2.8 to 3.46 GHz. Each core is based on the Nehalem (Westmere) micro-architecture. Hyperthreading enables the Dual Core CPU to handle 4 threads at once (for a better usage of the pipeline). Therefore, the i7-640M is related to the other i5 and i3 dual core CPUs and not the quad-core i7 CPUs.
A feature of the new Core i7-640M is the integrated graphics card called Intel HD Graphics (GMA HD) and memory controller. Both are on a separate die that is still manufactured in 45nm whereas the CPU die is already manufactured in the new 32nm process.
The 32nm cpu cores of the Westmere generation can also process some new instructions to accelerate AES encryptions. Compared to the slower i5 versions without AES features, the 3DMark Vantage Communication Score showed a significant increase with AES enabled CPUs.
The integrated Intel Graphics Media Accelerator HD (GMA HD) graphics card is clocked with 500-733 MHz and performs clearly faster than the old GMA 4500MHD. A GeForce 9400M (ION) should still be a bit faster (especially as Nvidia and ATI cards have a better driver support than Intel up to now).
The power consumption of 35 Watt TDP (max.) counts for the whole package and therefore it is clearly better than the 35 Watt TDP of the Core 2 Duo T-series (CPU alone).
|Intel Core i7-680UM||Intel Core i7-640M|
|Intel Core i7||Intel Core i7|
|: Core i7 Arrandale|
|1467 - 2533 MHz||2800 - 3460 MHz|
|512 KB||512 KB|
|4 MB||4 MB|
|2 / 4||2 / 4|
|81+144 mm2||81+114 mm2|
|105 °C||105 °C|
|Turbo Boost (2.40 GHz max), Hyper Threading, Enhanced Speedstep, integrated GMA HD 166-500MHz||Turbo Boost, Hyper Threading, Enhanced Speedstep, integrierte GMA HD 500-733MHz, Dual Channel DDR3 memory controller|
|$317 U.S.||$346 U.S.|
|Intel Core i7 680UM||Intel Core i7 640M|