S.E.C.C.2 Package Type
The S.E.C.C.2 package is similar to the S.E.C.C. package except the S.E.C.C.2 uses less casing and does not include the thermal plate. The S.E.C.C.2 package was used in some later versions of the Pentium II processor and Pentium III processor (242 contacts).
FC-PGA2 Package Type
FC-PGA2 packages are similar to the FC-PGA package type, except these processors also have an Integrated Heat Sink (IHS). The integrated heat sink is attached directly to the die of the processor during manufacturing. Since the IHS makes a good thermal contact with the die and it offers a larger surface area for better heat dissipation, it can significantly increase thermal conductivity. The FC-PGA2 package is used in Pentium III and Intel Celeron processor (370 pins) and the Pentium 4 processor (478 pins).
S.E.C.C. Package Type
S.E.C.C. is short for Single Edge Contact Cartridge. To connect to the motherboard, the processor is inserted into a slot. Instead of having pins, it uses goldfinger contacts, which the processor uses to carry its signals back and forth. The S.E.C.C. is covered with a metal shell that covers the top of the entire cartridge assembly. The back of the cartridge is a thermal plate that acts as a heatsink. Inside the S.E.C.C., most processors have a printed circuit board called the substrate that links together the processor, the L2 cache and the bus termination circuits. The S.E.C.C. package was used in the Intel Pentium II processors, which have 242 contacts and the Pentium® II Xeon™ and Pentium III Xeon processors, which have 330 contacts.
S.E.C.C.2 Package Type
The S.E.C.C.2 package is similar to the S.E.C.C. package except the S.E.C.C.2 uses less casing and does not include the thermal plate. The S.E.C.C.2 package was used in some later versions of the Pentium II processor and Pentium III processor (242 contacts).
Socket 478 (mPGA478B)
Socket 478 (mPGA478B) is a Pin Grid Array (PGA) socket for microprocessors based on Intel NetBurst architecture. This socket was introduced in August 2001 as replacement for short-lived socket 423. The socket 478 supports desktop and mobile Pentium 4 and Celeron processors from 1.4 GHz to 3.46 GHz with effective front-side bus frequencies 400 MHz - 1066 MHz (100 MHz - 266 MHz QDR). This socket was phased out in favour of socket 775 (LGA775).
One major difference between the socket 478 and older sockets is the socket size. The distance between pin holes in socket 478 is twice smaller than the distance between pin holes in the socket 370, which was used by older Celeron, Pentium and Pentium III families, and in the socket 423 used by first generation of Pentium 4 microprocessors. This results in much smaller socket size - only 1.38" x 1.38" (3.5 cm x 3.5 cm). Another difference between socket 478 and earlier sockets is the arrangement of pins. Pentium and newer CPUs, including socket 423 Pentium 4 microprocessors, had pins arranged as two grids where one grid was diagonally shifted relative to another grid by 1/2 of the distance between pins. In mPGA478B the pins are arranged as one grid, that is the same way as in Intel 80486 and older microprocessors.
The mPGA478B has grid size 26 x 26 with a 14 x 14 section removed from the center of the grid. Two pin-holes in one corner of the socket are plugged, so there is only one way to install the CPU. The total number of pins is (26 x 26) - (14 x 14) - 2 = 478.
Supported processors
Celeron Willamette (1.5 GHz - 2 GHz)
Celeron Northwood (1.5 GHz - 2.8 GHz)
Celeron D in 478-pin micro FC-PGA4 package (2.13 GHz - 3.2 GHz)
Desktop Intel Pentium 4 (1.4 GHz - 3.4 GHz)
Desktop Intel Pentium 4 Exteme Edition (3.2 GHz - 3.46 GHz)
Mobile Celeron (1.2 GHz - 2.5 GHz)
Mobile Pentium 4 processors in micro FC-PGA4 package (2.4 GHz - 3.46 GHz)
Mobile Pentium 4-M processors (1.4 GHz - 2.6 GHz)
Note: All processors are in 478-pin micro FC-PGA2 package, unless stated otherwise.
Mobile Pentium III-M and Pentium M microprocessors use different type of socket. There are no CPUs from other manufacturers compatible with socket 478.
Compatible package types
478-pin micro FC-PGA2 (with integrated heatspreader)
478-pin micro FC-PGA4 (with integrated heatspreader)
Please note that there are three different 478-pin packages, and only one of those packages is compatible with socket 478. The picture on the right shows the package that fits into the mPGA478B socket.
Upgrading socket 478 motherboards
Even though there are many Pentium 4 and Celeron CPUs that will fit into your motherboard, not all of them may be supported by the board. To determine the fastest processor you can upgrade to you'll need to:
- Determine manufacturer and model of your motherboard,
- Search on manufacturer's website for the motherboard model.
For upgrade information for ASUS, DFI, ECS, Gigabyte Technology, Jetway, MSI and PC Chips motherboards please check CPU-Upgrade motherboard database.
