The following sections in this chapter describe the function and physical components of the P–brick, and explain how to add and replace PCI cards in the P–brick:
The P–brick is a 4U I/O expansion subsystem that supports a maximum of 12 3.3-volt or universal hot-pluggable PCI cards.
The following are the P–brick's internal components and front panel items (Figure 6-1 shows the items located on the P–brick front panel):
Internal components:
Power board. Provides the power to the P–brick.
PCI motherboard. Houses the components and slots (and carriers) in which you can install PCI cards.
Front panel items:
L1 controller and display. L1 controller generates P–brick status and error messages that appear on the liquid crystal display (LCD).
On/Off switch with LED. Press this button to turn on the P–brick internal components. Alternatively, you can turn on the P–brick internal components at an L2 controller display or at a system console.
L1 controller switches and LEDs:
On/Off switch LED. Lights green when the P–brick internal components are on and turns off when they are off.
Service required LED. Lights orange to indicate that an item is broken or not operating properly (for example, a fan is off), but the P–brick is still operating.
Failure LED. Lights red to indicate that a system failure has occurred and the P–brick system is down.
Fans.
The power board contains the logic components of the L1 controller, voltage regulator modules (VRMs), and a DC-to-DC converter. The VRMs and the DC-to-DC converter, convert the incoming 48 VDC to voltage levels required by the components within the brick. See Appendix A, “Technical Specifications” for more details.
The P–brick's 12 PCI slots are on the PCI motherboard. Three Xbridge ASICs interface between two Crosstown2 ports and the PCI cards. Each Crosstown2 port transmits 1.2 GB/sec each direction and can connect to a Crosstown2 port on a C–brick. The PCI motherboard also contains a serial ID EEPROM that contains component information.
The L1 controller monitors and controls the environment of the P–brick. It consists of a display, logic components, and an internal cable. The display is located on the front of the P–brick. The P–brick's L1 controller logic components are on the power board. The internal cable connects the display to the logic components.
For general information about the L1 controller, see Chapter 3, “System Control ” of this guide.
Figure 6-2 shows the location of the power-on switch, PCI card slots, connectors, and LEDs on the P–brick rear panel.
The P–brick rear panel has the following items:
Power switch. Moving the power switch to the 1 position powers on the P–brick's L1 controller, and moving it to the 0 position powers off the P–brick's L1 controller. Powering on the L1 controller lights the 12 VDC LED green.
48 VDC and 12 VDC LEDs. The power switch must be in the ON (1) position for these LEDs to be on. The 12 VDC lights green when the L1 controller is powered on and operating, and the 48 VDC lights green when the rest of the I–brick internal components are powered on and operating. To power on the internal components, press the On/Off switch located on the L1 controller's front panel.
PWR (power) connector. Connects to the power bay to give power to the P-brick.
PCI slots. Use these slots to install and replace PCI cards onto your server system. See “PCI Card Description and Installation”. The PCI card slots are numbered bus 1 through bus 6. Each bus has two slots, labeled 1 and 2, as shown in Figure 6-3. All slots can accommodate 66 MHz or 33 MHz PCI cards. If a PCI bus contains both a 33-MHz card and a 66-MHz card, however, both slots of that bus run at 33 MHz.
PWR (power) LED. Lights green when the PCI card carrier is installed securely and is getting power.
Fault LED. Lights orange when a fault occurs with the PCI card.
XIO 10 and XIO 11 connectors. These connectors connect the P–brick to a C–brick. As an option, the second connector can be connected to another C–brick to create a dual-ported P–brick, which would provide greater bandwidth.
XIO 10 and XIO 11 connector LEDs. Light yellow when the connector is cabled securely to the C–brick device. Light green when the connection is negotiated with the device with which the connector is cabled.
The PCI card slots on the motherboard are numbered bus 1 through bus 6. Each bus has two slots, labeled 1 and 2, as shown in Figure 6-3.
Each bus has two slots that operate with 66-MHz or 33-MHz cards. If a PCI bus contains both a 33-MHz card and a 66-MHz card, both slots of that bus run at 33 MHz. The PCI bus supports 32-bit and 64-bit PCI cards at the same time. Separate buses enable the P–brick to run 66-MHz devices in the same brick as 33-MHz devices.
For maximum bandwidth, PCI cards are distributed across all six PCI buses when they are integrated at the factory.
The SGI Origin 3000 server systems support various PCI cards that can be purchased from SGI or from other manufacturer. Each PCI card is mounted in a carrier so that you can slide the PCI cards into and out of the brick. The PCI cards connect to the PCI motherboard when the PCI carrier is fully inserted into the brick.
Table 6-1 lists currently supported PCI cards from SGI.
Marketing Code | Description |
|---|---|
PCI-SER-10002 | Serial card |
PCI-SCSI-DF-2P | Ultra SCSI high-voltage differential 2-port |
PCI-SCSI-U3-2P | Ultra3 SCSI low-voltage differential 2-port (3.3 V) |
PCI-FC-1POPT-A | Fibre channel with fiber optic cable, 66 MHz |
PCI-FC-1PCOP-A | Fibre channel with copper cable, 66 MHz |
PCI-ATMOC3-1P | ATM OC3 |
PCI-ATMOC12-1P | ATM OC12 |
PCI-GIGENET-C | Gigabit Ethernet (copper) |
PCI-GIGENET-OR | Gigabit Ethernet (optical) |
PCI-AUD-D1000 | Digital audio |
The PCI carrier is designed to support most PCI cards. The carrier can be adjusted to accommodate different size PCI cards. (A description on how to make these adjustments is described within the installation procedure.)
When the P–brick is shipped, any PCI cards that were ordered are installed with carriers, and any unoccupied PCI slots are populated with empty PCI carriers. PCI carriers must be present in nonpopulated PCI slots to maintain an even airflow through the PCI slots and to protect against electromagnetic interference (EMI).
The PCI card is hot-pluggable, which means that although you need not power off the rack or the P–brick to add or replace a PCI card, you do need to power off the individual PCI card (the slot) in which you will replace a PCI card. The PCI card is powered off and powered on with the pci L1 controller command. For details, see “pci ” in Appendix B.
 | Warning: Before installing, operating, or servicing any part of this product, please read the “Safety Instructions” in Appendix D. |
 | Caution: It is recommended that you use a grounding wrist strap while installing a PCI card. |
To add or replace a PCI card for the system, follow these steps:
Using the pci L1 controller command, power off the PCI card (the slot) in which you will replace the PCI card.
Pull the handle on the empty PCI carrier straight out to extract it from a PCI slot, as shown in Figure 6-4.
If you are replacing a card, gently pull the existing PCI card from the carrier. If adding a PCI card, extract the PCI carrier's metal filler, by pushing down on it as shown in Figure 6-5. This filler covers the area where your PCI card's connectors will protrude out to the rear panel of the P–brick.
If the PCI card you want to install does not fit the carrier, using a Phillips screwdriver, loosen the three screws and adjust the carrier guide bar up or down as needed (see Figure 6-6).
Mount your new or replacement PCI card into the carrier using the guides on the guide bar, as shown in Figure 6-7.
Insert the PCI carrier carrying the PCI card horizontally into the vacant slot, using the slot guides, as shown in Figure 6-8.
Pushing horizontally on the PCI carrier's seating bar, as shown in Figure 6-9, seats the PCI card securely in the slot. After the card is installed, you will need to power on the PCI card (slot) using the pci L1 controller command.
