HPE ProLiant DL360 Gen11 PCIe Risers & Expansion

PCIe Expansion Overview

The HPE ProLiant DL360 Gen11 provides PCIe 5.0 expansion through its primary and optional secondary risers. The standard primary butterfly riser is included with CTO chassis and provides two PCIe 5.0 x16 slots connected to CPU 1.

An optional secondary riser adds PCIe Slot 3 and requires a second processor. HPE offers both full-height and low-profile secondary riser configurations. All DL360 Gen11 riser card slots use a physical x16 PCIe form factor with full x16 lanes of PCIe 5.0 electrical bandwidth.

PCIe Riser Options

The QuickSpecs identify the standard embedded primary riser, two optional secondary risers, and a standalone primary riser kit intended for field upgrades.

Standard Primary Riser

The standard primary butterfly riser is embedded in all CTO and BTO DL360 Gen11 servers. A separate riser option does not need to be ordered for a normal new server configuration.

Primary Riser Slot Priority

When only the standard primary riser is installed, PCIe Slot 1 has first priority and PCIe Slot 2 has second priority for x16, x8, x4, and x1 PCIe adapters.

P48901-B21 Full-Height Secondary Riser

The HPE ProLiant DL360 Gen11 x16 Full Height Riser Kit P48901-B21 is referred to by HPE as the Secondary FH riser. It provides PCIe Slot 3 as a PCIe 5.0 x16 full-height slot.

• A second processor is required.
• Slot 3 provides PCIe 5.0 x16 connectivity.
• Slot 3 supports full-height cards up to 9.5 inches or half-length cards.
• Installing the secondary full-height riser makes primary PCIe Slot 2 unavailable.
• If both 4-port networking using Base-T/full-height adapters and a half-height internal PCIe controller are selected, the Secondary FH riser cannot be selected.

Full-Height Secondary Riser Configuration

With P48901-B21 installed, the server provides two usable full-height PCIe slots: Slot 1 on the primary riser and Slot 3 on the secondary riser. Slot 2 is unavailable.

Full-Height Riser Slot Priority

When P48901-B21 is installed, Slot 1 has first PCIe adapter priority and Slot 3 has second priority.

P48903-B21 Low-Profile Secondary Riser

The HPE ProLiant DL360 Gen11 x16 LP Riser Kit P48903-B21 is the Secondary Low Profile riser. It adds PCIe Slot 3 while allowing primary PCIe Slot 2 to remain available.

• A second processor is required.
• Slot 3 provides PCIe 5.0 x16 connectivity.
• Slot 3 is low-profile and supports cards up to 9.5 inches or half-length cards.
• GPU support on this riser is limited to a maximum of 75W according to the riser information table.

Low-Profile Secondary Riser Configuration

With P48903-B21 installed, the DL360 Gen11 can provide three x16 PCIe slots. Slot 1 is full-height while Slots 2 and 3 are low-profile. HPE notes that Slot 2 is not available in the EDSFF CTO server.

The same Slot 1, Slot 3, Slot 2 priority order applies to x16, x8, x4, and x1 PCIe adapters. When two internal controllers are configured, HPE gives Slot 1 first priority and Slot 2 second priority; Slot 3 is not supported for the second controller in this configuration.

P75407-B21 Primary Riser Field Upgrade Kit

The HPE ProLiant Compute DL360 Gen11/Gen12 x16 Primary Riser Kit P75407-B21 is a standalone field-upgrade option. It is not intended for factory installation.

• The kit is ordered through Ad-hoc and ships as a standalone item rather than being installed in the server.
• Every DL360 Gen11 CTO server already includes a primary riser, so P75407-B21 is not required when ordering a normal CTO server.
• The kit is also compatible with the HPE ProLiant DL360 Gen12 as a primary riser upgrade kit.
• HPE identifies the kit as a field-upgrade option that can replace the Slot 1 and Slot 2 primary riser and enable a supported 4-port SFP adapter in Slot 2.

Maximum PCIe Card Configurations

The maximum number of usable PCIe cards changes depending on the selected secondary riser and whether the rear NS204i-u boot device enablement kit occupies the Slot 2 area.

NS204i-u and PCIe Expansion

The HPE NS204i-u Rear Cable Kit P54702-B21 directly affects PCIe expansion. Installing the hot-plug NS204i-u requires removal of the original PCIe Slot 2 cage, making Slot 2 unavailable.

When the rear NS204i-u configuration is used, PCIe Slot 1 remains available. PCIe Slot 3 can also be made available as a low-profile slot by installing the P48903-B21 Secondary LP Riser. HPE also states that the secondary full-height riser and the NS204i-u Rear Cable Kit cannot be selected together.

PCIe Adapter Slotting Rules

HPE provides explicit installation priorities for PCIe devices in the DL360 Gen11.

1. Install an x16 electrical-bandwidth card in an x16 electrical slot.
2. Install an x8 electrical card in an x8 electrical slot when applicable.
3. An x8 electrical card can be installed in an x16 electrical slot.

HPE also establishes card-type priorities when multiple PCIe devices compete for available slots.

Important PCIe Slot Restrictions

• The SR932i-p P47184-B21 full-height adapter can only be installed in PCIe Slot 1 because of its fixed cable length.
• PCIe stand-up Tri-Mode controller adapters can only be installed in Slot 1 or Slot 2.
• When a stand-up Tri-Mode controller is installed, an HHHL low-profile GPGPU should be installed in Slot 3.
• PCIe Slot 2 supports HHHL low-profile cards only.
• 4-port Base-T NICs are not supported in Slot 2 because of a mechanical constraint.
• If the NS204i-u Rear Cable Kit P54702-B21 is installed, PCIe Slot 2 is unavailable.
• All PCIe slots support Wake-on-LAN.

4-Port Network Adapter Slot Restrictions

Four-port network adapters have additional mechanical restrictions. HPE specifically states that the low-profile 4-port Base-T adapters P51178-B21 and P21106-B21 cannot be installed in PCIe Slot 2.

For shipments before May 2025, HPE documents possible left-port interference with a low-profile 4-port SFP NIC installed in Slot 3 when Slot 2 contains the primary riser cage or NS204i-u rear cable enablement hardware. HPE recommends using the secondary full-height riser for certain multi-adapter configurations, selecting an OCP 4-port SFP adapter instead, or using the P75407-B21 standalone primary riser field-upgrade option to enable a supported 4-port SFP adapter in Slot 2.

EDSFF PCIe Expansion Considerations

The 20 EDSFF CTO configuration has additional PCIe limitations because PCIe connectivity is also used by the front storage configuration. The QuickSpecs specifically state that PCIe Slot 2 is not available for the EDSFF CTO server in the three-slot secondary low-profile riser configuration.

EDSFF configurations using the SR932i-p Tri-Mode controller can also require the P48901-B21 Full Height Riser Kit when the controller is installed in PCIe Slot 2 or Slot 3 with the applicable EDSFF controller enablement configuration.

Primary vs. Secondary Riser

The primary riser is standard equipment and connects to CPU 1. The optional secondary risers connect PCIe Slot 3 to CPU 2, which is why a second processor is mandatory whenever a secondary riser is selected.

The choice between P48901-B21 and P48903-B21 primarily determines the physical form factor of Slot 3 and whether Slot 2 remains available. P48901-B21 provides a full-height Slot 3 but removes Slot 2 from use. P48903-B21 provides a low-profile Slot 3 while allowing Slot 2 to remain available when another component does not occupy it.