Intel Pentium III 1333 socket: Socket 370

What the Pentium III 1333 is

The Intel Pentium III 1333 is a 1333 MHz single-core desktop processor from December 2001. It runs one P6 Tualatin core at 1333 MHz with no turbo, so 1 core gives 1 thread. Cache is 256 KB of full-speed L2 with 32 KB of L1 on a 130 nm process. Power is rated at 30 W in a Socket 370 FC-PGA2 package with part numbers SL5VX and SL6BZ on a 133 MHz front side bus with a 10x multiplier at 1.475 V.

A round 10x ratio at the top of the 133 MHz bus gives the 1333 clean timing on late boards, which is why it headed performance Socket 370 towers before the 1400 arrived. Intel placed the 1333 in December 2001 with the 1400. The chip supports MMX, SSE and hardware prefetch with Data Prefetch Logic.

High clocks with a steady 30 W envelope suit late Socket 370 performance desktops with SDRAM and fast AGP cards. The mature 130 nm process keeps the 1333 MHz mark within the stock cooler class. That is why the 1333 shipped in enthusiast towers with discrete graphics.

Socket and motherboard compatibility

The 1333 fits Socket 370 late performance desktops with Tualatin support. It needs a 370-pin FC-PGA2 Tualatin-ready board with a 133 MHz bus and a BIOS that lists Pentium III 1333. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Late performance towers are the natural match. Boards listing SL5VX accept the chip with a 30 W cooler. Coppermine-era boards with no Tualatin voltage tables refuse the 1.475 V core, so the board revision decides.

Memory, PCIe and cooling

Memory is PC133 SDRAM through the board chipset, matched to the board DIMM sockets. The CPU has no memory controller, so the chipset sets speed and timing. Late 815E B-step boards commonly run aggressive PC133 timings for 1333 MHz parts.

A 133 MHz front side bus ties the CPU to the chipset, while AGP 4X and PCI hang off the chipset. No PCIe lanes originate on the die. Cooling uses the Socket 370 lug clip on the FC-PGA2 spreader with a cooler rated for 30 W.

Upgrade paths

On the same socket, a move to a Pentium III 1400 such as Intel Pentium III 1400 keeps the board and memory when the support list names it. The 1400 adds 67 MHz at 31 W with a 10.5x ratio, so the cooler stays close. A Pentium III 1200 such as Intel Pentium III 1200 drops 133 MHz at equal power.

A move to Pentium III-S doubles cache with server strings when the board lists S parts. The Socket 370 page lists the Tualatin range for planning.