System Ports; Pci Adapters; Pci Express - IBM Power Systems S822LC Technical Overview And Introduction

The two x16 slots that are provided by the internal PCIe riser (Slot 1 and Slot 3) can be
populated with GPU adapters (NVIDIA) or can be used for any high-profile (not LP) adapters.
Mixing of GPU and other high-profile adapters on the internal PCIe riser is supported.
Only LP adapters can be placed in LP slots. An x8 adapter can be placed in an x16 slot, but
an x16 adapter cannot be placed in an x8 slot. One LP slot must be used for a required
Ethernet adapter (#5260, #EL3Z, or #EN0T).

1.12 System ports

The system board has one 1 Gbps Ethernet port, one Intelligent Platform Management
Interface (IPMI) port and a VGA port, as shown in Figure 1-14 on page 24.
The integrated system ports are supported for modem and asynchronous terminal
connections with Linux. Any other application that uses serial ports requires a serial port
adapter to be installed in a PCI slot. The integrated system ports do not support IBM
PowerHA® configurations. The VGA port does not support cable lengths that exceed
3 meters.

1.13 PCI adapters

This section covers the various types and functions of the PCI adapters that are supported by
the Power S822LC servers.

1.13.1 PCI Express

Peripheral Component Interconnect Express (PCIe) uses a serial interface and allows for
point-to-point interconnections between devices (by using a directly wired interface between
these connection points). A single PCIe serial link is a dual-simplex connection that uses two
pairs of wires, one pair for transmit and one pair for receive, and can transmit only one bit per
cycle. These two pairs of wires are called a
these configurations, the connection is labeled as x1, x2, x8, x12, x16, or x32, where the
number is effectively the number of lanes.
The PCIe interfaces that are supported on this server are PCIe Gen3, which are capable of
16 GBps simplex (32 GBps duplex) on a single x16 interface. PCIe Gen3 slots also support
previous generation (Gen2 and Gen1) adapters, which operate at lower speeds, according to
the following rules:
Place x1, x4, x8, and x16 speed adapters in the same size connector slots first, before
mixing adapter speed with connector slot size.
Adapters with lower speeds are allowed in larger sized PCIe connectors, but larger speed
adapters are not compatible in smaller connector sizes (that is, a x16 adapter cannot go in
an x8 PCIe slot connector).
PCIe adapters use a different type of slot than PCI adapters. If you attempt to force an
adapter into the wrong type of slot, you might damage the adapter or the slot.
POWER8 based servers can support two different form factors of PCIe adapters:
PCIe low profile (LP) cards, which are used with the Power S822L server.
lane
. A PCIe link can consist of multiple lanes. In
Chapter 1. Architecture and technical description
25