Motherboard Description

1.12.1.1SW_ON

This 2-pin header connects to a front panel power switch. When the switch is closed, the power supply turns on. If a mechanical switch is connected to this header, it must apply a momentary ground to the SW_ON header pin in order to signal the supply to turn on or off. Because of the motherboard’s internal debounce circuitry, the ground must be applied for at least 50ms. At least two seconds must pass before the power supply will recognize another on/off signal (to prevent “double clicking”).

1.12.1.2Sleep/Resume

When Advanced Power Management (APM) is activated in the BIOS and the Operating System’s APM driver is loaded, Sleep mode (Standby) can be entered in one of three ways:

An optional front panel “Sleep/Resume” button

A user defined keyboard hot key

Prolonged computer inactivity

The Sleep/Resume button is supported by a 2-pin header located on the front panel I/O connector. Closing the “Sleep” switch generates an SMI (System Management Interrupt) to the processor which immediately goes into System Management Mode (SMM).

The front panel “Sleep mode” switch must be a momentary two pin SPST type that is normally open. The function of the Sleep/Resume button can also be achieved by using a keyboard hot-key sequence, or by a time-out of the inactivity timer. Both the keyboard hot key and the inactivity timer are programmable in the BIOS Setup (timer is set to 10 minutes by default). To reactivate the computer, or “Resume”, the user must simply press the sleep/resume button again, or use the keyboard or PS/2 mouse. Mouse activity only “wakes up” the computer if a mouse driver is loaded. While the computer is in Standby or “sleep” mode, it is fully capable of responding to and servicing external interrupts (such as in-coming FAX) even though the monitor only turns on if a user interrupt (keyboard/mouse) occurs as mentioned above.

1.12.1.3Infrared Connector

Serial port 2 can be configured to support an IrDA module with a 5 pin header connector. Once configured for IrDA, the user can transfer files to or from portable devices such as laptops, PDAs and printers using application software such as LapLink. The IrDA specification provides for data transfers at 115 Kbps from a distance of 1 meter. Consumer IR is also supported by the same connector.

1.12.1.4Hard Drive LED

This 3-pin, keyed header can be connected to a front panel LED to indicate when hard drive activity is taking place. When the hard drive is being accessed, the HDACTIVE pin (J2A1-15) goes low.

1.12.1.5Power-ON LED

This 2-pin header can be connected to a front panel LED to indicate when power is applied to the motherboard. When the motherboard is powered up, power is applied to the PWRDRV pin (J2A1-20) to light the front panel LED.

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Intel AP440FX specifications Swon, Sleep/Resume, Infrared Connector, Hard Drive LED, Power-ON LED

AP440FX specifications

The Intel AP440FX is a pivotal motherboard that was released in the late 1990s, designed to support the Intel Pentium II and Pentium III processors. Known for its robust performance and versatile functionalities, the AP440FX became a popular choice among computer enthusiasts and system builders during its time.

One of the defining features of the Intel AP440FX is its support for the Intel 440FX chipset. This chipset provided improved system performance through its use of a 66 MHz front-side bus, which allowed for faster data transfer between the CPU and the memory. The motherboard was equipped with two DIMM slots capable of supporting a maximum of 512 MB of SDRAM, providing users with the flexibility to choose the amount of memory they required for their applications.

Another notable characteristic of the AP440FX motherboard is its integrated support for various peripheral interfaces. It comes equipped with multiple ISA and PCI slots, allowing users to expand their system capabilities through the addition of various cards. The presence of two USB ports, which were relatively new at the time of its release, gave users access to a wider range of peripherals and external devices.

The Intel AP440FX also features an integrated IDE controller, enabling connection for hard drives and optical drives without the need for additional controller cards. This integrated solution simplified storage management for users and contributed to the overall efficiency of the system. The motherboard also supported SCSI through optional daughter cards, catering to users who required high-speed data transfer and reliable disk storage solutions.

Moreover, the AP440FX was designed with future upgrades in mind. Its BIOS supported plug-and-play installations, allowing users to easily configure new hardware components without extensive troubleshooting. Additionally, the ATX form factor of the motherboard contributed to its compatibility with a wide range of cases and power supplies.

In terms of power management, the Intel AP440FX incorporated advanced features such as ACPI (Advanced Configuration and Power Interface), which allowed for better power efficiency and management of power states. This feature was particularly beneficial for users looking to reduce energy consumption and improve the overall longevity of their systems.

All in all, the Intel AP440FX represented a significant advancement in motherboard technology during its era. Its combination of robust performance, upgradeability, and support for new technologies made it a popular choice for users looking to build powerful and efficient computing systems.