Intel Pentium 4-M 2.40 socket: Socket 478

What the Pentium 4-M 2.40 is

The Intel Pentium 4-M 2.40 is a 2.4 GHz single-core mobile processor from January 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. The package is Socket 478 for notebooks with DDR slots. This page omits a TDP rating because no opened source states power for the 2.40 P4-M bin, while nearby 2.20 TO 2.60 P4-M bins use different power handling.

The 2.40 P4-M uses a 400 MT/s front side bus with a 24x multiplier and SpeedStep trimming clocks on battery. Intel sold it in January 2003 as a mainstream notebook chip with a 35 mm by 35 mm package. The chip supports MMX, SSE and SSE2 with SpeedStep. Mobile Pentium 4 2.40 parts at the same 2.4 GHz offer 59.8 W operation with different power tables for desktop-replacement bodies, so chassis decides which 2.4 GHz mobile suits the board.

SpeedStep with a small package defines the thin notebook appeal against Mobile Pentium 4 desktop-replacement parts at higher power. The P4-M trims voltage and clocks at idle, which extends battery life in mainstream bodies. That is why P4-M parts suited road use while Mobile P4 parts needed wall power.

Socket and motherboard compatibility

The Pentium 4-M 2.40 fits Socket 478 notebooks with DDR memory and P4-M BIOS support. It needs a notebook Socket 478 board with SpeedStep paths. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Mainstream DDR notebooks are the natural match. Maker lists decide fit, since Mobile P4 2.40 parts at similar clocks need larger cooling.

Memory, PCIe and cooling

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

A 400 MT/s bus ties the CPU to the mobile chipset, while graphics hangs off the chipset. No PCIe lanes originate on the die. Cooling is the notebook heat pipe for the exact mainstream chassis with SpeedStep control.

Upgrade paths

On Socket 478 the mobile steps are P4-M 2.50 and 2.60 parts where listed. Mobile Pentium 4 2.40 parts offer desktop-replacement alternatives at higher power. Pentium M Dothan parts on Socket 479 offer far lower power for thin bodies. The 2.40 removes with the socket mechanism, so swaps need no solder work.