Intel’s “Core 2 Duo” is best-in-class when it comes to power consumption and heat dissipation. The TDP for the E6700 is 65 Watt, and for the X6800 70 Watt. TDP or “Thermal Design Power” gives the amount of power the thermal solution in a PC should be capable of dissipating to ensure that the CPU is operating within its specified thermal envelope. Intel’s TDP rating is not referring to the maximum amount of power a CPU can consume under full load, but under average working conditions. This means that a CPU under full load can consume far more power than its rated TDP. An E6700 running at the default frequency of 2.66 GHz is easily consuming under 100% load up to 145 Watt. With the Intel retail heatsink and an ambient temperature of around 24~26 C it the E6700 is running at around 52C to 55C.