Intel Core i7-840QM vs vs unknown

Because of the Turbo Mode, the CPU is clocked with up to 3.2 GHz (if only one core is used, 2.93 for two cores, and 2 ghz with 4 cores) and therefore can perform very well in single core applications like older games.

The Core i7 line has an integrated memory controller for DDR3 bars (1066 or 1333) supporting a maximum of 8 GB. Therefore, the memory performance is very good (compared to older CPUs with external memory controllers). Still, this also leads to the higher TDP of the whole chip. ECC memory is not supported by the 840QM.

The Core micro-architecture is still very similar to the one used in the Core 2 CPUs, therefore the performance per MHz (neglecting the integrated memory controller, hyperthreading and Turbo Boost) is similar.

The power consumption of up to 45 Watt (TDP) is quite high for a laptop CPU and because of the Turbo Mode, the power consumption should reach these high values. Therefore, the CPU is only suited for large laptops.