10Super I/O controller. This Low Pin Count (LPC) interface provides the commonly used Super I/O functionality. The chipset supports a high-performance floppy disk controller for a 360K/720K/1.44M/ 2.88M floppy disk drive, a multi-mode parallel port, two standard compatible UARTs, a Standard Infrared (SIR), one MPU-401 UART mode compatible MIDI/game port, and a Flash ROM interface.

11DIP switches. This 10-switch Dual Inline Package (DIP) allows you to set the CPU external frequency.

12Flash EEPROM. This 2Mb firmware contains the programmable BIOS program.

13South bridge controller. Referred to as the Intel I/O Controller Hub 2 (ICH2) of the Intel 845D chipset, this controller provides the I/O subsystem that allows access to the rest of the system. The ICH2 integrates I/O functions such as system bus interface, Ultra ATA/100, Low Pin Count (LPC) interface, Universal Serial Bus (USB) 1.1 interface, PCI interface, and CNR interface.

14ASUS ASIC. This chip performs multiple system functions that include hardware and system voltage monitoring, IRQ routing, among others.

15Onboard LED. This onboard LED lights up if there is a standby power on the motherboard. This LED acts as a reminder to turn off the system power before plugging or unplugging devices.

16CNR slot. This slot is specifically designed for the Communications and Networking Riser (CNR) card. The CNR supports V.90 analog modem, HPNA, USB Hub, and the 10BASE-T/100BASE-TX Ethernet networking.

17Audio controller. This C-Media 6-channel PCI audio chip supports legacy audio and HRTF 3D positional audio functions. The chip also supports 24-bit S/PDIF In (0.5~5V) and S/PDIF Out (44.1K and 48K formats) professional digital audio interface.

(on audio models only)

18PCI slots. These six 32-bit PCI 2.2 expansion slots support bus master PCI cards like SCSI or LAN cards with 133MB/s maximum throughput.

19AGP slot. This Accelerated Graphics Port (AGP) slot supports 1.5V AGP4X mode graphics cards for 3D graphical applications.

ASUS P4B266 motherboard user guide

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