Intel SE7520JR2 3.4.1.4PCI Riser Slots, 3.4.1.1P32-A: 32-bit, 33-MHzPCI Subsystem, 3.4.1.3P64-Express:Dual x4 PCI Bus Segment

Functional Architecture						Intel® Server Board SE7520JR2
		Table 7: PCI Bus Segment Characteristics
	PCI Bus Segment	Voltage	Width	Speed	Type	PCI I/O Card Slots
	P32-A	5 V	32-bits	33 MHz	PCI	None. Internal component use only
	P64-A	3.3 V	64-bits	100 MHz	PCI-X	Common riser slot capable of supporting full-
						length PCI-X or PCI-E add-in cards
	P64-B	3.3 V	64-bits	100 MHz	PCI-X	One riser slot supporting only low-profile add-
						in cards
	P64-Express	Differential	64-bits	Dual x4	PCI-E	Common riser slot capable of supporting full-
						length PCI-X or PCI-E add-in cards

3.4.1.1P32-A: 32-bit, 33-MHz PCI Subsystem

All 32-bit, 33-MHz PCI I/O is directed through the ICH5-R. The 32-bit, 33-MHz PCI segment provided by the ICH5-R is known as the P32-A segment. The P32-A segment supports the following embedded devices:

•2D/3D Graphics Accelerator: ATI Rage XL Video Controller

•SIO Chip: National Semiconductor* PC87417 Super I/O

•Hardware monitoring sub-system: SMBUS

3.4.1.2P64-A and P64-B: 64-bit, 100MHz PCI Subsystem

Two peer 64-bit PCI-X bus segments are directed through the PXH PCI Bridge. The first PCI-X segment, P64-A, supports the interface for the on-board LSI* 53C1030 Ultra320 SCSI controller, in addition to supporting up to three PCI-X add-in cards from the full-height PCI riser slot. The second PCI-X segment, P64-B, supports the interface to the on-board Intel® 82546GB dual port Gigabit network controller, in addition to up to three PCI-X add-in cards from the low profile PCI riser slot.

3.4.1.3P64-Express: Dual x4 PCI Bus Segment

The full height riser slot supports both X4 and X8 PCI-E type widths. In a 2U system, the baseboard supports two x4 PCI-E slots. In a 1U system, the baseboard supports one x8 PCI-E slot.

The BIOS performs link training with PCI-E devices during boot and checks the resulting status. If it detects that a port is not connected to a PCI-E device, it disables the port.

3.4.1.4PCI Riser Slots

The Server Board SE7520JR2 has two riser slots capable of supporting riser cards for both 1U and 2U system configurations. Because of board placement resulting in different pin orientations, and expanded technology support associated with the full-height riser, the riser slots are proprietary and require different riser cards.

The low profile riser slot (J5F1) utilizes a 202-pin connector. It is capable of supporting up to three low profile PCI-X add-in cards, depending on the riser card used. The P64-B bus can support bus speeds of up to 100MHz with up to two PCI-X 100MHz cards installed. The bus speed will drop to 66MHz when three PCI-X 100MHz cards are installed, or will match the card speed of the lowest speed card on the bus. Ie) If any of the add-cards installed on the P64B bus

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