Hub Interface; Revision 1.0; Pci-X Hub (Pxh); Full-Height Riser Slot - Intel SE7520JR2 Technical Manual

Intel® Server Board SE7520JR2
GB/s. One x8 interface is used as the interconnect between the MCH and PXH, while the other
is configured as two separate x4 interfaces to the full height riser slot.
The E7520 MCH is a root class component as defined in the PCI Express Interface
Specification, Rev 1.0a. The PCI Express interfaces of the MCH support connection to a variety
of bridges and devices compliant with the same revision of the specification. Refer to the Server
Board SE7520JR2 Tested Hardware and OS List for the add-in cards tested on this platform.
3.2.1.4

Hub Interface

The MCH interfaces with the Intel 82801ER I/O Controller Hub 5-R (ICH5-R) via a dedicated
Hub Interface which supports a peak bandwidth of 266MB/s using a x4 base clock of 66 MHz.
3.2.2

PCI-X Hub (PXH)

The PXH provides the data interface between the MCH and two PCI-X bus segments over a
high-speed PCI-Express x8 link. The PCI-Express interface is compliant with the PCI Express
Base Specification rev 1.0 and provides a maximum realized bandwidth of 2GB/s in each
direction simultaneously, for an aggregate of 4 GB/s.
The PCI-X interfaces of the PXH comply with the following:
• PCI-X Addendum to the PCI Local Bus Specification Revision 1.0b
•
Mode 1 of the PCI-X Electrical and Mechanical Addendum to the PCI Local Bus
Specification Revision 2.0a
• PCI-X Protocol Addendum to the PCI Local Bus Specification Revision 2.0a
For conventional PCI Mode, the PXH supports PCI bus frequencies of 66 MHz, 100 MHz, and
133 MHz.
On the Server Board SE7520JR2 each of the two PCI-X interfaces (PCI Bus A and PCI Bus B)
is independently controlled to operate in either a conventional PCI or PCI-X mode. PCI Bus A is
routed to control I/O from the full-height riser slot and the LSI* 53C1030 Dual Channel SCSI
controller and is capable of supporting both PCI-X Mode 1 and Mode 2 interfaces depending on
the riser card used. PCI Bus B is routed to control I/O from the low profile riser slot and the
82546GB Dual GB Ethernet controllers.
3.2.2.1

Full-height Riser Slot

Using Intel® Adaptive Slot Technology, the full height riser slot is a proprietary 280-pin slot
connector with both PCI-X signals from the PXH and PCI-Express signals from the MCH routed
to it. Depending on the riser card used, the slot is able to support both PCI-X and/or PCI-
Express add-in cards. The board placement of this slot allows risers to support full-height, full-
length add-in cards.
3.2.2.2

Low Profile Riser Slot

The low profile riser slot is a standard 202-pin slot connector supporting PCI-X signals from the
PXH. Because of available board clearances, riser cards can only support low-profile add-in
cards with this slot.

Revision 1.0

C78844-002
Functional Architecture
33