AMD Athlon XP 1900+ socket: Socket 462

What the Athlon XP 1900+ is

The AMD Athlon XP 1900+ is a 1600 MHz single-core desktop processor from November 2001. It runs one K7 Palomino core at 1600 MHz with no turbo, so 1 core gives 1 thread. Cache is 256 KB of L2 on a 180 nm process. Power is rated at 68 W in a Socket 462 package with part number AX1900DMT3C on a 266 MT/s front side bus with a 12x multiplier at 1.75 V. The cpu_list November 2001 date matches the table November 5, 2001, and the monthly value is used here.

Palomino 1900+ tops the early Athlon XP stack before Thoroughbred parts arrived in June 2002, sharing its 1600 MHz clocks with lower power Thoroughbred 1900+ parts at 52.5 W on 130 nm. AMD sold the Palomino version at 269 dollars in November 2001. The chip supports MMX, SSE and Enhanced 3DNow.

High power with an older process marks the end of the Palomino line. The 68 W rating against 52.5 W on Thoroughbred 1900+ parts at the same 1600 MHz reflects 1.75 V operation on 180 nm. That is why Thoroughbred replacements run cooler at identical ratings.

Socket and motherboard compatibility

The Athlon XP 1900+ Palomino fits Socket 462 DDR boards with a 266 MT/s bus and Palomino support. It needs Model 6 microcode. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Early DDR towers are the natural match. Boards listing Palomino 1900+ accept the chip with a 68 W cooler.

Memory, PCIe and cooling

Memory is DDR through the board chipset in a single channel, matched to the 266 MT/s bus. The CPU has no controller.

A 266 MT/s 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 lug clip with a 68 W heatsink.

Upgrade paths

On Socket 462 the steps are Palomino 2000+ and 2100+ parts. Thoroughbred 1900+ parts offer the same clocks at lower power where listed. Beyond Socket 462 a move to Socket 754 needs a new board. The 1900+ lifts with the lever, so swaps need no solder work.