Intel Pentium M 1.40 socket: Socket 479

What the Pentium M 1.40 is

The Intel Pentium M 1.40 is a 1400 MHz single-core mobile processor from March 2003. It runs one P6 Banias core at 1400 MHz with no turbo, so 1 core gives 1 thread. Cache is 1 MB of L2 with 64 KB of L1 on a 130 nm process. Power is rated at 22 W in a Socket 479 micro FCPGA package on a 400 MT/s front side bus with a 14x multiplier.

A 100 MHz lift over the 1.30 at the same 22 W keeps battery draw flat, which is why the 1.40 suited buyers who wanted a small speed gain with no cooler change. Intel launched the 1.40 on March 12, 2003 with the 1.30, 1.50 and 1.60 parts. The chip supports MMX, SSE, SSE2 and Enhanced SpeedStep with Deeper Sleep states.

Balanced clocks with a large cache suit Centrino business laptops with DDR memory and wireless. The 14x ratio keeps the 400 MT/s bus in spec. That is why the 1.40 shipped in mainstream corporate laptops with docking stations.

Socket and motherboard compatibility

The 1.40 fits Socket 479 business laptops with Banias support. It needs a 479-pin board with a 400 MT/s bus and a BIOS that lists Pentium M 1.40. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Corporate DDR laptops are the natural match. Boards listing Pentium M 1.40 accept the chip with a 22 W pipe. Because the 1.40 shares power with the 1.30, swaps between the two rarely need a new pipe, but the BIOS string must still match.

Memory, PCIe and cooling

Memory is DDR through the board chipset, matched to the board slots. The CPU has no memory controller, so the chipset sets the type and speed. Corporate 855 boards commonly run DDR266 pairs for 400 MT/s parts.

A 400 MT/s front side bus ties the CPU to the chipset, while AGP and PCI hang off the chipset. No PCIe lanes originate on the die. Cooling uses the laptop heat pipe for the exact chassis, rated for 22 W with a 100 degree C junction limit.

Upgrade paths

On the same socket, a move to a Pentium M 1.50 such as Intel Pentium M 1.50 keeps the laptop when the support list names it. The 1.50 adds 100 MHz at 24.5 W, so the pipe and power tables must cover the step up. A Pentium M 1.30 on the same list drops 100 MHz at equal power.

A move to Core Solo Yonah needs Socket M with a new board. The Socket 479 page lists Banias, Dothan and Yonah paths for planning.