2. Special Features Of The Celeron M Compared To The Pentium M

There's a separate logo for notebooks with the Celeron M

The Celeron M will initially come in a 1.3 GHz and a 1.2 GHz version. Both models require a power supply of 1.356 volts and the notebook's processor cooling system must be designed for a thermal design power (TDP) of 24.5 watts.

At the same time, an ultra-low voltage version of the Celeron M will be offered with an operating point of 800 MHz / 1.004 Volts. The manufacturer rates the thermal design power of this CPU at barely seven watts. Intel is planning a Micro-FCBGA package for the ULV version. Consequently, all units based on the ULV model can only be upgraded later in exceptional cases. This is because the processor is soldered to the motherboard.

In the Celeron M, the cross-hatched part of the L2 cache, which takes up more than one-third of the space, serves no purpose. The same goes for the Speedstep function block.

It's true that the Celeron M is based on the Banias core, like its big brother the Pentium M. However, only 512 kB of the 1 MB L2 cache on the Celeron M die are addressable. The remaining 50% of the cache is deactivated during the CPU's validation process. With regard to the size of the die, there is no difference between the two processors, since the space taken by the cache is identical.

Take a good look: Due to the identical die sizes, only the label on the FCPGA packaging can differentiate the CPUs. This is because a 1 MB sized, fully functional L2 cache requires just as much space as a 1 MB sized L2 cache in which only 50% of the memory cells work.