Intel Pentium 4 HT Extreme Edition 3.46 socket: LGA 775

What the Pentium 4 EE 3.46 is

The Intel Pentium 4 HT Extreme Edition 3.46 is a 3.466 GHz single-core enthusiast processor with Hyper-Threading from October 2004. It runs one NetBurst Gallatin core at 3.466 GHz with no turbo, so 1 core gives 2 threads. Cache is 512 KB of L2 plus 2 MB of L3 on a 130 nm process. Power is rated at 110.7 W in an LGA 775 package with part numbers BX80532PH3460FS and JM80532PH0992M. The cpu_list 110 W value matches the table 110.7 W after rounding, and the table value is used here.

The 3.46 is the only Pentium 4 Extreme Edition with a 1066 MT/s front side bus, using a 266 MHz clock with a 13x multiplier at 1.287 V to 1.40 V. Intel sold it at 999 dollars in October 2004. The faster bus lifts memory bandwidth over 800 MT/s EE parts at the same cache size. The chip supports MMX, SSE and SSE2 with Hyper-Threading. No Socket 478 version exists at 3.46 GHz, so LGA 775 boards are mandatory.

Bus speed plus L3 cache made the 3.46 the fastest NetBurst single core for gaming in late 2004. The 1066 MT/s link feeds the 2 MB L3 faster than 800 MT/s EE 3.40 parts, which shows in memory bound games. That combination justified the flagship price before Prescott 2M EE 3.73 parts arrived in 2005.

Socket and motherboard compatibility

The EE 3.46 fits LGA 775 enthusiast desktops with DDR or DDR2 memory, a 1066 MT/s bus and a BIOS that lists Gallatin EE parts. It needs a land grid board with 1066 MT/s chipset support, not a Socket 478 board. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

High-end LGA 775 towers with Intel 925X chipsets and PCIe graphics are the natural match. Boards listing the EE 3.40 normally accept the 3.46 with a BIOS update for the faster bus and a cooler rated above 110 W. Older 800 MT/s-only boards may boot yet run the bus below spec without proper chipset support.

Memory, PCIe and cooling

Memory is DDR or DDR2 through the board chipset, with dual channel operation giving full bandwidth for the 1066 MT/s bus. The CPU has no memory controller, so chipset and BIOS set the usable memory type.

A 1066 MT/s front side bus ties the CPU to the chipset, while PCIe x16 carries graphics on LGA 775 boards. No PCIe lanes originate on the die. Cooling uses the LGA 775 load plate with four points to the board and a heatsink rated above 110 W. The 72 mm screw spacing decides cooler fit, and strong case airflow matters at 3.466 GHz.

Upgrade paths

On LGA 775 the EE 3.46 tops Gallatin before Prescott 2M EE 3.73 parts at 3.73 GHz with 2 MB of L2 cache. Standard Prescott 560 parts at 3.6 GHz offer similar clocks without the L3 cache at lower cost. Beyond NetBurst a move to Pentium D dual cores or Core 2 parts needs chipset and BIOS support on LGA 775. The 3.46 lifts with the load plate open, so swaps need no solder work.