Socket 423 socket: CPUs, chipsets and cooler fit
Socket 423 is the Intel pin grid array socket that carried the first Willamette Pentium 4 processors. It uses 423 pins with a 400 MT/s front side bus and paired with i850 RDRAM and i845 SDRAM chipsets.
Quick facts
| Maker | Intel |
|---|---|
| Package type | PGA |
| Contacts | 423 |
| Package size | n/a |
| Introduced | November 2000 |
| Status | Legacy |
| Memory | RDRAM and SDRAM through the board chipset |
| PCIe from the CPU | Front side bus 400 MT/s to the chipset; expansion hangs off the chipset |
| Cooler mounting holes | Board specific (Socket 423 bracket) |
| Replaces | Socket 370 |
| Replaced by | Socket 478 |
Overview
The socket served desktops from November 2000 to late 2001 before Socket 478 replaced it. Its short life makes boards and coolers specific to the early Pentium 4 generation.
Processor generations
| Codename | Marketing name | Years | Notes |
|---|---|---|---|
| Willamette | Pentium 4 Willamette | 2000 to 2001 | 180 nm single cores with 256 KB of L2 cache on a 400 MT/s bus, including the 1.3 GHz part at 51.6 W from January 2001. |
Who Socket 423 serves
Socket 423 targets early Pentium 4 desktops with RDRAM performance paths. Towers with i850 chipsets pair the socket with PC800 RDRAM pairs and AGP graphics. The short production run keeps used boards tied to Willamette power tables.
Memory and cooling
Memory is RDRAM and SDRAM through the board chipset at the 400 MT/s bus rate. Cooling uses the Socket 423 bracket with coolers rated for 52 W class parts. Retention parts differ from Socket 478, so the exact board kit matters.
CPUs on Socket 423
2 processor pages in the database, newest first.
| Processor | Cores / threads | Base / boost | TDP | Launched |
|---|---|---|---|---|
| Intel Pentium 4 1.8 | 1 / 1 | 1.8 GHz | 67 W | Jul 2001 |
| Intel Pentium 4 1.3 | 1 / 1 | 1.3 GHz | 52 W | Jan 2001 |
Frequently asked questions
Which processors fit Socket 423?
Willamette Pentium 4 single cores with 256 KB of L2 cache on a 400 MT/s bus, including the 1.3 GHz part at 51.6 W from January 2001 covered here. Faster Willamette parts also shipped in Socket 478.
Is Socket 423 the same as Socket 478?
No. Socket 423 has 423 pins for early Willamette Pentium 4 chips, while Socket 478 has 478 pins for later Willamette, Northwood and Prescott parts. The packages are physically different.
What memory does Socket 423 use?
RDRAM and SDRAM through the board chipset, commonly RDRAM pairs on i850 boards for 400 MT/s parts. The board sets the exact type.
How many PCIe lanes does Socket 423 provide?
No lanes come from these CPUs. A 400 MT/s bus ties the CPU to the board chipset, while AGP and PCI hang off the chipset.
Sources and verification
Facts last checked against these sources on . Page last edited on .