Gateway Solutions- Networking, Hardware & Security : Computer Hardware-Intel desktop CPU sockets and slots

Intel desktop CPU sockets and slots

Socket or slot Description

Slot 1 242-pin 2.8V and 3.3V connector for Pentium IIs, IIIs, and Celerons

Slot 2 330-pin 1.5V to 3.5V connector for Pentium II and III Xeons

Socket 423 423-pin 1.7V and 1.75V for Pentium 4s

Socket 478 478-pin 1.7V and 1.75V for Pentium 4s and Celerons

Socket 603 603-pin 1.5V and 1.7V for Pentium 4 Xeons, and Xeon MPs

Socket 604 604-pin for Pentium 4 Xeons

Socket 611 611-pin 3.3V for Itanium 2s

Socket 755 755-pin for Pentium 4s and Celerons

Socket 775 775-pin for Pentium 4s, Celerons, Core 2 Duo, Core 2 Extreme, and Core 2 Quads

Socket B or Socket 1366 1366-pin for Core i7s

Table 2.7

AMD desktop CPU sockets and slots

Socket or slot Description

Socket A or 462-pin 1.1V to 1.85V for Duron and Athlons

Socket 462

Socket AM2 940-pin for Athlon, Athlon X2, and Semprons

Socket AM2+ 940-pin for Athlon X2, Phenom X3, and Phenom X4s

Socket AM3 940-pin for Phenom II X3 and Phenom II X4s

Socket 754 754-pin for Athlon and Semprons

Socket 939 939-pin for Athlon and Athlon X2s

1207-pin

ATX power supply connectors

Connector Notes Voltage(s)

24-pin Main ATX power connector to the motherboard +3.3, +5, +12, –12

20-pin Main power connector to the motherboard +3.3, +5, –5, +12, –12

15-pin SATA connector +3, +5, +12

8-pin 12V for CPU +12V

6-pin PCIe video; connects to PCI video adapter +12V

6-pin Sometimes labeled as AUX; connects to the motherboard +3.3, +5

if it has a connector

4-pin Molex Connects to peripheral devices such as hard drives and +5, +12

CD/DVD drives

4-pin Berg Connects to peripheral devices such as the floppy drive +5, +12

4-pin Sometimes labeled as AUX or 12V; connects to the +12V

motherboard for CPU

3-pin Used to monitor fan speed N/A

Figure 4.8 shows a few ATX power supply connectors.

Figure 4.9 shows the ATX power supply connectors. Figure

4.10 (on page 116) illustrates the compatibility between the

two ATX motherboard connector standards. Notice in

Figure 4.10 how the power cable is only one connector,

notched so the cable inserts into it one way only. This is a

Not all 24-pin motherboard connectors

much better design than older power supplies where two

accept 20-pin power supply connectors

connectors were used that could be reversed. Also, notice

You can purchase a 24-pin to 20-pin power adapter.

that a power good signal (labeled PWR_OK in the figure)

A Web site containing information regarding power

goes to the motherboard. When the computer is turned on,

supply form factors is http://www.formfactors.org.

part of POST is to allow the power supply to run a test on

each of the voltage levels. The voltage levels must be cor-

rect before any other devices are tested and allowed to initialize. If the power is OK, a power good sig-

nal is sent to the motherboard. If the power good signal is not sent from the power supply, a timer

chip on the motherboard resets the CPU. Once a power good signal is sent, the CPU begins executing

software from the BIOS. Figure 4.10 also shows the +5vsb connection to provide standby power for

features such as Wake on LAN or Wake on Ring (covered later in the chapter).

Tech

Tip

Power Supply Form Factors

4-pin CPU power connector

Figure 4.8

SATA power connector

115

6-pin PCIe power connector

ATX power supply

PCIe power

connector: 6-pin

Fan speed

monitor connector

4-pin floppy

power connector

Figure 4.9

4-pin Molex

power connector

Main power

connector: 24-pin

ATX power supply connectors

Tech

Tip

A high-quality power supply delays sending the power good signal until all of the power sup-

ply’s voltages have a chance to stabilize. Some cheap power supplies do not delay the power good

signal. Other cheap power supplies do not provide the power good circuitry at all, but instead tie

five volts to the signal, sending a power good signal even when it is not there.

The number and quantity of connectors available on a power supply depends on the power

supply manufacturer. If a device requires a Berg connector and the only one available is a Molex,

a Molex-to-Berg connector converter can be purchased. If a SATA device needs a power connec-

tion, a Molex-to-SATA converter is available. Figure 4.11 shows a Molex-to-Berg converter and a

Molex-to-SATA converter.

The power supply connectors can connect to any

Power converters and Y connectors are

device; there is not a specific connector for the hard

good to have in your tool kit

drive, the CD/DVD drive, and so on. If there are not

When a service call involves adding a new device,

enough connectors from the power supply for the

having various power converters available as part of

number of devices installed in the computer, a Y power

your tool kit is smart.

connector can be purchased at a computer or elec-

tronics store. The Y connector adapts a single Molex

connector to two Molex connectors for two devices. Verify that the power supply can

output enough power to handle the extra device being installed. Figure 4.12 shows a Y power

connector.

116