Intel Core Duo T2400 socket: Socket M

What the Core Duo T2400 is

The Intel Core Duo T2400 is a 1.83 GHz mobile dual core from January 2006. It runs two Yonah cores at a fixed 1.83 GHz through an 11x multiplier on a 667 MT/s bus, so 2 cores give 2 threads with no turbo step. Cache is 2 MB of shared L2 on a 65 nm process. Power is rated at 31 W for the standard voltage socketed part.

The T2400 stood one rung above the mainstream T2300 in the launch lineup, adding about 170 MHz per core at the same bus speed and envelope. That lift showed in thread heavy desktop applications of early 2006, where two cores at 1.83 GHz pulled clear of single core Solo parts. Notebook makers placed it in upper mainstream Napa machines with discrete mobile graphics options beside chipset graphics.

Yonah is a 32-bit line, with 64-bit support arriving only on the Merom parts that later shared this socket. The two cores share the single 2 MB cache, so cache heavy pairs of threads contend more than on later split cache designs. The locked multiplier holds the 11x ratio steady on every board whose BIOS lists the exact sSpec.

Socket and motherboard compatibility

The socketed T2400 fits the Socket M lever socket (Socket M) on Napa boards with the 945PM or 945GM chipset. The 478-contact Micro-FCPGA package seats with zero insertion force and locks under the screw lever. The board BIOS must list the exact sSpec, since Napa revisions set which steppings boot, and the vendor CPU support page decides a swap.

The T2400 shipped both as a socketed Micro-FCPGA part for Socket M and as a soldered Micro-FCBGA part. Only the Micro-FCPGA package fits the lever socket, while the soldered variant belongs to Socket 479 boards and cannot be socketed later. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules for socketed mobile parts.

Memory, PCIe and cooling

Memory is DDR2 through the board chipset in two channels. DDR2-667 SO-DIMMs are the standard match for a 667 MT/s Yonah on Napa boards, and the board fixes the slot count plus the maximum capacity. The notebook vendor list sets the tested module size for the exact model.

The front side bus runs at 667 MT/s between the CPU and the mobile chipset. No PCIe lanes come from the T2400 itself, while board graphics and expansion slots hang off the chipset at speeds the board maker sets. Machines with discrete mobile graphics still drive the display through the board, since the CPU carries no graphics block.

Cooling is the notebook vendor heat pipe assembly for the exact chassis, sized for the 31 W envelope with a side vent. Retail desktop towers do not mount to mobile sockets, so the fan and pad set must come from the notebook maker. Paste or pad replacement follows the service manual for the exact model.

Upgrade paths

On Socket M the step up from a T2400 is a faster 667 MT/s dual core such as the Core Duo T2500 at 2.0 GHz, the T2600 at 2.17 GHz, or the T2700 at 2.33 GHz. Each keeps the 31 W envelope while lifting clocks, so chassis qualified for the T2400 thermal design stay in range. A swap must stay within the thermal design the chassis was qualified for, and the BIOS must list the new sSpec.

A larger step is a Merom Core 2 Duo such as the T7200 at 2.0 GHz on the same Socket M, which adds 64-bit support with 4 MB of L2 cache. Napa boards need a Merom aware BIOS revision for those parts. Past Merom the path leaves the socket for a Socket P Santa Rosa board, as described in the Socket vs chipset: what decides whether a CPU works guide.