Intel Pentium III 1133S socket: Socket 370

What the Pentium III 1133S is

The Intel Pentium III 1133S is an 1133 MHz single-core server processor from June 2001. It runs one P6 Tualatin-S core at 1133 MHz with no turbo, so 1 core gives 1 thread. Cache is 512 KB of full-speed L2 with 32 KB of L1 on a 130 nm process. Power is rated at 29 W in a Socket 370 FC-PGA2 package with part numbers SL5LV and SL5PU on a 133 MHz front side bus with an 8.5x multiplier at 1.45 V.

Double cache over desktop 1133 parts at matching clocks gives the 1133S an edge in database tasks, which is why it headed entry dual-processor boards in mid 2001. Intel placed the 1133S in June 2001 with the 1000S server parts. The chip supports MMX, SSE and two-way SMP on server chipsets.

Mid server clocks with a large cache and a modest envelope suit dual Socket 370 boards with ECC SDRAM. The 1.45 V core keeps pair thermals in check. That is why the 1133S shipped in workgroup servers with paired chips.

Socket and motherboard compatibility

The 1133S fits Socket 370 dual server boards with Tualatin-S support. It needs a 370-pin FC-PGA2 server board with a 133 MHz bus and a BIOS that lists Pentium III-S parts. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Dual server boards are the natural match. Boards listing Pentium III 1133S accept one or two chips with 29 W coolers each. Single desktop boards may run one chip, but the second socket and VRM stages only exist on server boards.

Memory, PCIe and cooling

Memory is PC133 ECC SDRAM through the board chipset, matched to the board DIMM sockets. The CPU has no memory controller, so the chipset sets ECC paths and speed. Dual boards commonly interleave ECC pairs across both processor paths.

A 133 MHz front side bus ties each CPU to the chipset, while PCI-X and PCI hang off the chipset. No PCIe lanes originate on the dies. Cooling uses Socket 370 lug clips on FC-PGA2 spreaders with coolers rated for 29 W each and ducted airflow.

Upgrade paths

On the same socket, a move to a Pentium III 1266S such as Intel Pentium III 1266S keeps the board and memory when the support list names it. The 1266S adds 133 MHz at 30 W with the same 512 KB cache. A Pentium III 1133 such as Intel Pentium III 1133 halves cache and drops SMP paths.

A move to Pentium III 1400S keeps the server line at higher clocks when the board VRM allows. The Socket 370 page lists the server range for planning.