Intel Pentium 4 HT 551 socket: LGA 775
The Intel Pentium 4 HT 551 uses the LGA 775 socket. It is a 115 W single-core Prescott desktop part at 3.4 GHz with Hyper-Threading and 1 MB of L2 cache for performance towers.
- Socket
- LGA 775
- Launched
- June 2005
- Cores and threads
- 1 and 2
- Base power
- 115 W
- Codename
- Prescott
- Segment
- Desktop
- Family
- Intel Pentium 4 HT
- Clocks
- 3.4 GHz
Intel Pentium 4 HT 551 specifications
| Cores | 1 |
|---|---|
| Threads | 2 |
| Core architecture | Prescott cores on 90 nm |
| Clocks | 3.4 GHz (no turbo) |
| Cache | 1 MB L2 |
| Processor base power (TDP) | 115 W |
| Manufacturing process | 90 nm |
| Memory support | DDR2 through the board chipset |
| Front side bus | 800 MT/s |
| PCI Express | PCIe from the board chipset |
| Integrated graphics | None (board video where fitted) |
| Multiplier | Locked |
| Package | LGA 775 |
Motherboard compatibility
Intel Pentium 4 HT 551 needs a motherboard with a LGA 775 socket. Chipset by chipset data for this codename is not recorded yet. See the LGA 775 chipset list and the board maker's CPU support list.
LGA 775 at a glance
| Type | LGA, 775 contacts |
|---|---|
| Package size | 37.5 × 37.5 mm |
| Introduced | 2004 |
| Memory | DDR, DDR2 or DDR3, depending on the motherboard chipset |
| Cooler mounting holes | 72 × 72 mm |
What the Pentium 4 HT 551 is
The Intel Pentium 4 HT 551 is a 3.4 GHz single-core desktop processor from June 2005. It runs one NetBurst core at 3.4 GHz with Hyper-Threading, so 1 core gives 2 threads. Cache is 1 MB of L2 on a 90 nm process. Power is rated at 115 W on LGA 775.
The 551 served performance LGA 775 towers on an 800 MT/s bus with a 17x multiplier at about 278 dollars launch price. It exists because buyers wanted Hyper-Threading at 3.4 GHz where the board cools 115 W.
Socket and motherboard compatibility
The 551 drops into LGA 775 boards with DDR2 memory and a BIOS that lists Prescott 5xx parts, such as 915 boards. Boards need voltage regulator support for the 115 W envelope. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.
Memory, PCIe and cooling
Memory is DDR2 through the board chipset in two channels.
An 800 MT/s front side bus ties the CPU to the chipset. PCIe slots hang off the chipset.
Cooling is a 115 W rated LGA 775 heatsink on the 72 mm mount.
Upgrade paths
On LGA 775 the upgrade is the Pentium 4 HT 561 at 3.6 GHz in the same 115 W class, or the Intel Pentium 4 HT 541 at 3.2 GHz for 84 W operation. Beyond LGA 775 a move to a newer platform needs a new board and memory.
Frequently asked questions
What socket does the Pentium 4 HT 551 use?
LGA 775, on DDR2 boards with a Prescott-aware BIOS and 115 W support.
How many cores does the Pentium 4 HT 551 have?
One core and 2 threads at 3.4 GHz with Hyper-Threading and 1 MB of L2 cache.
What memory works with the Pentium 4 HT 551?
DDR2 through the board chipset in two channels.
Sources and verification
Facts last checked against these sources on . Page last edited on .