HP 525 5/XX Transfer Rates Versus Modes of Operation, Configuration Connections to Data Cables

2 System Board - (SiS Chipset) (Part Number: D4051-63001)

Devices on the PCI Bus

Minitower	Configuration		Connections to Data Cables
	One hard disk drive	1. Bootable hard disk drive:		Master connector, HDD data cable
	Two hard disk drives	1. Bootable hard disk drive:		Master connector, HDD data cable
		2.	Second hard disk drive:	Slave connector, HDD data cable
	Three hard disk	1.	Bootable hard disk drive:	Master connector, HDD data cable
	drives	2.	Second hard disk drive:	Slave connector, HDD data cable
		3.	Third hard disk drive:	Master connector, CD-ROM data cable
	One hard disk drive	1.	Bootable hard disk drive:	Master connector, HDD data cable
	One CD-ROM drive	2.	CD-ROM drive:	Master connector, CD-ROM data cable
	Two hard disk drives	1.	Bootable hard disk drive:	Master connector, HDD data cable
		2.	Second hard disk drive:	Slave connector, HDD data cable
	One CD-ROM drive	3.	CD-ROM drive:	Master connector, CD-ROM data cable
	Three hard disk	1.	Bootable hard disk drive:	Master connector, HDD data cable
	drives	2.	Second hard disk drive:	Slave connector, HDD data cable
	One CD-ROM drive	3.	Third hard disk drive:	Master connector, CD-ROM data cable
		4.	CD-ROM drive:	Slave connector, CD-ROM data cable
	Two hard disk drives	1.	Bootable hard disk drive:	Master connector, HDD data cable
		2.	Second hard disk drive:	Slave connector, HDD data cable
	Two CD-ROM drives	3.	CD-ROM driver:	Master connector, CD-ROM data cable
		4.	Second CD-ROM drive:	Slave connector, CD-ROM data cable

The BIOS uses the auto-detected drive information to select the fastest configuration supported by each installed IDE drive.

Transfer Rates Versus Modes of Operation

The IDE controller supports 32-bit Windows and DOS I/O transfers (many IDE controllers use Windows integral IDE driver which only supports 16-bit I/O transfers). It supports programmed I/O (PIO) modes up to mode 4 and direct memory access (DMA) modes up to mode 2 (giving a cycle time of 120 ns, and a transfer rate of 16.7 MB per second, in both cases).

The five PIO modes allow the following transfer rates:

Mode	0	1	2	3	4
Cycle time (ns)	600	383	240	180	120
Transfer rate (MBytes/s)	3.33	5.22	8.33	11.1	16.7

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