Dell OptiPlex 5055 Small Form Factor Owner's Manual

ASPM is the power management capability of hardware to effectively reduce usage of power by placing the PCI Express(PCIe) based serial link devices to low-power state when not in use.

ASPM is controlled by BIOS or the power management component of the operating system in two configurations.

• Disabled: PCIe devices operate on high-performance mode.
• L1 Mode: Bi-directional setting of the serially linked PCIe device to low-power state.
  • NOTE: This mode provides with higher power saving at expense of latency when re-establishing the connection.

The PCIe bus must be woken up from low-power mode to re-establish the connection with the device. This accounts for the latency, which is also referred to as ASPM exit latency.