Memory

View the status of the system memory.

Adaptive Double Device Data Correction (ADDDC) Sparing is a RAS function that provides more reliability of memory error correction in virtual lockstep mode. When the memory correctable error count reaches a pre-defined threshold, ADDDC will trigger virtual lockstep mode, which can significantly reduce performance.

For high frequency, low latency, or low jitter workloads, Lenovo generally recommends disabling ADDDC sparing for high performance.

ADDDC Sparing will not take effect if the system has x8 DIMMs or 9x4 value DIMMs or if memory is set to [Mirror mode] (Full or Partial).

Page Policy setting determines whether the memory controller keeps the last accessed page open.

• [Adaptive]: improves performance for applications with a highly localized memory access pattern.

• [Closed]: benefits applications that access memory more randomly.

Enable or disable DDR Memory Built-In Self Test (MBIST).

Enable or disable DRAM Post Package Repair (PRR).

Enable or disable memory test during normal boot.

Enable or disable Cold Boot Fast.

Enable or disable AC Boot Fast which is for AC boot only.

Memory traffic on the data bus is not random and can cause current “hot spots” on the DIMM. Memory data scrambling uses a data scrambling feature in the memory controller to create pseudo-random patterns on the data bus to reduce possibility of data-bit errors due to the impact of excessive current fluctuations

Patrol Scrub works in the background to proactively check DIMMs to repair correctable errors.

When enabled, Patrol Scrub takes effect at the end of POST.

Enable or disable dynamic ECC mode selection.

Select the memory speed.

• [Max]: maximizes performance.

• [Power Efficient]: offers a balance between performance and power.

• [Min]: maximizes power savings.

When a preset workload profile is selected, this setting is not changeable and is grayed out. To change the setting, select System Settings > Workload Profile > Custom first. Then, you can make change to this setting.

Select the memory refresh rate.

When a preset workload profile is selected, this setting is not changeable and is grayed out. To change the setting, select System Settings > Workload Profile > Custom first. Then, you can make change to this setting.

The Error check and scrub (ECS) function allows early detection of possible DRAM failures to avoid or reduce downtime.

• [Disabled]: Disables the ECS function.

• [Enabled]: Enables ECS without result collection.

• [Enable ECS with Result Collection]: Enables ECS with result collection.

View and configure the memory mirror state.