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RAM Installation & Dual-Channel

Seat DIMMs correctly and populate the right slots for dual-channel operation

A Reference Guide

The DIMM Notch (Key)

  • 1Every DDR DIMM has an off-center notch in its gold contact edge. The slot has a matching ridge.
  • 2The module can only enter one way. If it doesn't drop in smoothly, it is oriented backwards.
  • 3Never force a DIMM. Forced insertion risks bending pins and cracking the PCB.
  • 4DDR4 and DDR5 notch positions differ from each other and from DDR3. They are not interchangeable.

Seating Procedure

  • 1Open (press outward) the retention clips at both ends of the target slot.
  • 2Align the DIMM notch to the slot ridge and lower the module straight in.
  • 3Press down firmly and evenly on both ends simultaneously.
  • 4Both clips snap closed automatically when the DIMM is fully seated. Listen and feel for the click.
  • 5Visually confirm both clips are locked and the gold contacts are no longer visible.

Dual-Channel Population

  • 1Dual-channel requires a matched pair of DIMMs (same capacity, ideally same speed) in the correct paired slots.
  • 2Paired slots share the same color on the board. The CPU interleaves across both channels, doubling effective memory bandwidth.
  • 3Most boards with 4 slots pair them as: A1+B1 (secondary, lighter color) and A2+B2 (primary, darker color).
  • 4With only 2 sticks, manufacturers typically recommend the A2+B2 pair (slots 2 and 4, closest to the CPU) for best signal integrity.
  • 5Always consult the motherboard manual. Preferred slot order varies. A2+B2 is the most common default, not a universal rule.

Slot Color Guide & Common Errors

DIMM_A1: Channel A, secondary
DIMM_A2: Channel A, primary
DIMM_B1: Channel B, secondary
DIMM_B2: Channel B, primary
  • !Installing both sticks in A1+A2 (same channel) = single-channel only.
  • !Installing both sticks in B1+B2 (same channel) = single-channel only.
  • !For 4-stick installs, populate all four slots in one operation.

Your Mission

Loading mission...

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B Install the RAM

1

Open the retention clips on the target slots

In Progress

Click each slot you plan to use to open its retention clips. Clips must be open before a DIMM can be seated. Your mission specifies how many sticks to install.

Select the correct slots for your mission, then open their clips.

Motherboard: DIMM slots (click a slot to open clips)
LGA
2

Orient the DIMM: align the notch

Locked

The off-center notch in the DIMM must align with the ridge in the slot before seating. Which way does the DIMM face?

3

Seat the DIMMs: even pressure until clips snap

Locked

Click each open slot to seat a DIMM. Apply even downward pressure on both ends. The clips will snap closed automatically when fully seated.

Motherboard: click open slots to seat DIMMs
LGA
Available DIMMs
4

Verify dual-channel population

Locked

The system now reads the memory configuration. Click "Run POST Check" to verify the DIMMs are in the correct slots for the mission goal.