Intel Pentium 4 HT 3.06 socket: Socket 478

What the Pentium 4 HT 3.06 is

The Intel Pentium 4 HT 3.06 is a 3.06 GHz single-core desktop processor with Hyper-Threading from November 2002. It runs one NetBurst Northwood core at 3.06 GHz with no turbo, so 1 core gives 2 threads. Cache is 512 KB of L2 on a 130 nm process. Power is rated at 81.8 W in a Socket 478 package with part numbers SL6K7 and SL6JJ. The cpu_list June 2003 date and 110 W value differ from the table November 2002 and 81.8 W, and the table values are used here.

The 3.06 was the first desktop with Hyper-Threading, using a 533 MT/s front side bus with a 23x multiplier at 1.525 V to 1.55 V. Intel sold it at 637 dollars in November 2002. The chip supports MMX, SSE and SSE2 with Hyper-Threading. Mobile Pentium 4 HT 3.06 parts at the same clocks offer notebook packaging with different power tables, so board type separates the bins at identical frequency.

First Hyper-Threading status made the 3.06 a landmark for multitasking on single cores. The second thread hides memory latency during office and media tasks, which is why the 3.06 cost more than non-HT 3.06 GHz parts despite sharing cache.

Socket and motherboard compatibility

The Pentium 4 HT 3.06 fits Socket 478 desktops with DDR memory, a 533 MT/s bus and Northwood HT support. It needs a 478-pin board with Hyper-Threading paths. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Early DDR towers with 533 MT/s chipsets are the natural match. Intel 845PE boards accept the chip with an 81.8 W cooler. Later 800 MT/s boards normally run the chip with a BIOS update, since pin compatibility runs through the socket.

Memory, PCIe and cooling

Memory is DDR through the board chipset. The board sets speed and capacity.

A 533 MT/s bus ties the CPU to the chipset, while AGP handles graphics. No PCIe lanes originate on the die. Cooling uses the Socket 478 bracket with an 81.8 W heatsink.

Upgrade paths

On Socket 478 the steps are Northwood HT 3.20 and 3.40 parts on 800 MT/s buses. Mobile HT 3.06 parts offer notebook packaging. Beyond Socket 478 a move to LGA 775 needs a new board. The 3.06 lifts with the lever, so swaps need no solder work.