Intel Pentium III 1400S socket: Socket 370

What the Pentium III 1400S is

The Intel Pentium III 1400S is a 1400 MHz single-core server processor from January 2002. It runs one P6 Tualatin core at 1400 MHz with no Hyper-Threading, so 1 core gives 1 thread. Cache is 512 KB of L2 at full core speed on a 130 nm process with 47 million transistors. Power is rated at 32.2 W in a Socket 370 package with part numbers SL5XL and SL657 on a 133 MHz front side bus with a 10.5x multiplier at 1.45 V. The cpu_list 32 W and January 2002 values match the table 32.2 W and January 8, 2002 after rounding, and the table values are used here.

S marks 512 KB of L2 cache with dual-processor capability, which separates the 1400S from the 1400 with 256 KB for single-processor desktops at 31.2 W. Both run 1400 MHz on a 133 MHz bus, yet only S parts enable two-socket operation with server chipsets. Intel sold the 1400S at 315 dollars in January 2002. The chip supports MMX and SSE with PC133 ECC SDRAM DIMM support to 4 GB on Tualatin server boards.

Server cache with low power suited small dual-processor systems. Two 1400S parts give two cores with 1 MB of total L2 at 64.4 W of CPU power, which fit quiet rackmount cases with SDRAM memory. That is why the 1400S cost more than desktop Tualatin parts at the same clocks despite sharing frequency.

Socket and motherboard compatibility

The Pentium III 1400S fits Socket 370 blue Tualatin server boards with a 133 MHz bus and Tualatin-S BIOS support. It needs a board with dual-processor paths and 512 KB cache microcode. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Small SDRAM servers with ServerWorks chipsets are the natural match. Boards listing Tualatin-S 1400S accept the chip with a cooler rated for 32.2 W. Desktop Tualatin boards with single-processor-only firmware may seat the chip yet miss dual-processor paths.

Memory, PCIe and cooling

Memory is PC133 ECC SDRAM through the board chipset, with up to 4 GB across four DIMMs on Tualatin-S server boards. The CPU has no memory controller, so the chipset sets timing.

A 133 MHz 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 Socket 370 lug with a 32.2 W heatsink under the 180 gram mass cap. Fresh paste suits the small Tualatin die.

Upgrade paths

On Socket 370 the steps are limited, since the 1400S tops Tualatin-S with 512 KB. Desktop Tualatin 1400 parts with 256 KB offer the same clocks without dual-processor support. Celeron Tualatin parts offer smaller cache as value alternatives. Beyond Socket 370 a move to Socket 478 needs a new board with DDR memory. The 1400S lifts with the lever, so swaps need no solder work.