Intel Core i5-540UM vs Intel Core i5-470UM vs Intel Core i5-520UM

The Intel Core i5-540UM is a Ultra Low Voltage dual-core processor for small and light laptops. It is clocked with 1.2 - 2 GHz (if Turbo Boost is enabled). 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). AES, VT-d and Trusted Execution are activated (compared to the 430UM).

The Intel Core i5-470UM is a Ultra Low Voltage dual-core processor for small and light laptops. It is clocked with 1.3 - 1.8 GHz (if Turbo Boost is enabled). 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). AES, VT-d and Trusted Execution are deactivated for the 470UM, compared to the i7 UM CPUs.

The faster i5-560UM and i7-660UM are also clocked at 1.3 GHz but feature a higher TurboBoost frequency.

A feature of the new Core i5-520UM 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 i5-520UM is faster than a similar clocked Core 2 Duo (1.2 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 1.86 GHz is not very important. 

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.

The power consumption of 18 Watt TDP (max.) counts for the whole package and therefore it is clearly better than the 17 Watt TDP of the Core 2 Duo SL-series (CPU alone).