Intel Pentium III Xeon 800 5V-12V socket: Slot 2

What the Pentium III Xeon 800 5V-12V is

The Intel Pentium III Xeon 800 5V-12V is an 800 MHz single-core server processor from January 2000. It runs one P6 Cascades core at 800 MHz with no Hyper-Threading, so 1 core gives 1 thread. Cache is 256 KB of full-speed L2 with 32 KB of L1 on a 180 nm process with 28 million transistors. Power is rated at 25.4 W in a Slot 2 SECC cartridge on a 133 MT/s front side bus with a 6x multiplier on the 5V-12V regulator path.

The 133 MT/s bus with a low 6x ratio gives the 800 balanced throughput at modest power, which is why it suited dual workgroup servers in early 2000. Intel launched the Xeon 800 on January 12, 2000 at $901. The chip supports MMX, SSE and two-way SMP.

Mid server clocks with a fast bus suit Slot 2 workgroup boards with registered SDRAM. That is why the 800 5V-12V shipped in dual boxes.

Socket and motherboard compatibility

The 800 5V-12V fits Slot 2 workgroup servers with 5V-12V regulation. It needs a 330-lead SC330 board with a 133 MT/s bus and a BIOS that lists the 5V-12V 800 string. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Workgroup rack servers are the natural match. Boards listing the string accept cartridges with 25.4 W heatsinks.

Memory, PCIe and cooling

Memory is registered ECC SDRAM through the server chipset, matched to the board sockets. The cartridge has no memory controller. Workgroup boards commonly run ECC pairs.

A 133 MT/s front side bus ties each cartridge to the chipset, while PCI hangs off the chipset. No PCIe lanes originate on the cartridge. Cooling uses SECC heatsinks on the retention cage.

Upgrade paths

On the same slot, a move to a Pentium III Xeon 800 2.8V such as Intel Pentium III Xeon 800 2.8V keeps clocks and cache while changing regulator path. A Xeon 866 5V-12V such as Intel Pentium III Xeon 866 5V-12V adds clocks at higher power.

A move to Foster Xeon needs Socket 603. The Slot 2 page lists the range.