Intel Mobile Pentium 4 2.40 socket: Socket 478

What the Mobile Pentium 4 2.40 is

The Intel Mobile Pentium 4 2.40 is a 2.4 GHz single-core mobile processor from June 2003. It runs one NetBurst Northwood core at 2.4 GHz with no turbo and no Hyper-Threading on this rating, so 1 core gives 1 thread. Cache is 512 KB of L2 on a 130 nm process. Power is rated at 59.8 W in a Socket 478 package. The cpu_list 1/2 threads value differs from the table 1 thread, and the table single thread value is used here.

The 2.40 Mobile P4 uses a 533 MT/s front side bus with an 18x multiplier at 1.20 V to 1.55 V. Intel sold it at 186 dollars in June 2003 for desktop-replacement notebooks without SpeedStep savings. The chip supports MMX, SSE and SSE2. Pentium 4-M 2.40 parts at the same 2.4 GHz offer SpeedStep operation for mainstream notebooks, so power management separates the bins at identical frequency.

Desktop-replacement scope without SpeedStep explains the higher power than P4-M parts. The 59.8 W envelope needs a large heat pipe with wall power operation. That is why Mobile P4 parts suited large notebooks with desktop clocks, while P4-M parts suited road use with battery savings.

Socket and motherboard compatibility

The Mobile 2.40 fits Socket 478 desktop-replacement notebooks with a 533 MT/s bus and Mobile P4 support. It needs a notebook Socket 478 board with desktop-replacement power delivery. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Large DDR notebooks are the natural match. Maker lists decide fit, since P4-M 2.40 parts at the same clocks need SpeedStep paths instead.

Memory, PCIe and cooling

Memory is DDR through the board chipset with notebook slots. The CPU has no controller.

A 533 MT/s bus ties the CPU to the chipset, while graphics hangs off the chipset. No PCIe lanes originate on the die. Cooling is the large notebook heat pipe for 59.8 W operation.

Upgrade paths

On Socket 478 the mobile steps are Mobile Pentium 4 2.66 and 2.80 parts where listed. P4-M 2.40 parts offer SpeedStep alternatives at lower power. Pentium M Dothan parts on Socket 479 offer thin notebook paths. The 2.40 removes with the socket mechanism, so swaps need no solder work.