Intel Core 2 Duo T6600 vs Intel Core i7-2649M

The Intel Core i7-2649M is power efficient LV (Low Voltage) processor for laptops. The base frequency of 2.3 GHz is relatively low, but due to Turbo Boost 2.0, the CPU may clock up to 3.2 GHz (one core loaded, 2.9 GHz with both cores loaded). However, this is depending on the cooling and power consumption of the laptop. Due to HyperThreading, the i7-2649M is able to handle 4 threads in parallel. Compared to the similar called Core i7-2620M, the 2649M is slower but also needs less power (25W versus 35W TDP).

Sandy Bridge is the evolutionary successor of the Arrandale architecture. The most noteable improvements is the improved Turbo 2.0 and the integration of the graphics card into the 32nm CPU core. 

The integrated Intel HD Graphics 3000 clocked at 500 or 1100MHz (Turbo Boost). Due to the slower base clock rate, compared to HD Graphics 3000 in 35W and 45W processors (usually clocked at 650), the performance should be a bit lower.

The performance of the CPU should be a bit higher than a similar clocked Arrandale Core i7 LV. Therefore, the performance should a bit above the Core i3-390M if the Turbo can be used often.

The TDP of 25W (includes the integrated GPU and memory controller) allows the use of the 2649M CPU in thin notebooks.