Xserve: How to remove or install memory

Learn how to install additional memory or replace the memory in your Xserve.

This article has been archived and is no longer updated by Apple.

Choose your model


Applicable models

Xserve (Early 2009)

Memory specifications

This Xserve model has the following memory specifications:

Number of memory slots 12
Base memory 3 GB (three 1 GB DIMMs)
Maximum memory 48 GB
Memory card specifications - 1066 MHz DDR3 ECC (Error Correcting Code) DIMMs
- 1 GB, 2 GB, or 4 GB DIMMs (optimally, 6 or 12 identical DIMMs for a dual-CPU Xserve
and 3 or 6 identical DIMMs for a single-CPU Xserve)
Additional notes Important: Apple recommends that you use Apple-approved DIMMs. Other DIMMs might degrade the performance of the Xserve. DIMMs from older Xserve systems are not compatible with this Xserve. You can purchase Apple-approved memory online from the Apple Store at www.apple.com/store.


The 12 memory slots are labeled A1 through A6 and B1 through B6, in interleaved fashion. Single-CPU systems might not have B slots.
12 memory slots labelled

Removing or installing memory

For the best Xserve performance, install identical DIMMs as shown in the following table.

3 (single or dual CPU) A1 A2 A3 Slots for 3 DIMMs
4 (dual CPU) A1 A2
B1 B2
Slots for 4 DIMMs
6 (single CPU) A1 A2 A3 A4 A5 A6 Slots for 6 DIMMs (single)
6 (dual CPU) A1 A2 A3
B1 B2 B3
Slots for 6 DIMMs (dual)
8 (dual CPU) A1 A2 A3 A4
B1 B2 B3 B4
Slots for 8 DIMMs
10 (dual CPU) A1 A2 A3 A4 A5
B1 B2 B3 B4 B5
Slots for 10 DIMMs
12 (dual CPU) A1 A2 A3 A4 A5 A6
B1 B2 B3 B4 B5 B6
Slots for 12 DIMMs

For the best performance from a dual-CPU Xserve, install six or twelve identical DIMMs in the slots shown in the table above. For a single-CPU Xserve, install three or six identical DIMMs. The Memory Slot Utility should tell you if you could improve your DIMM configuration. The utility runs automatically the first time you start up the Xserve after changing the memory configuration. You can also run it at any time from /System/ Library/CoreServices/Memory Slot Utility.

Step 1: Open the Xserve

  1. Shut down the Xserve. Wait a few minutes to let the Xserve internal components cool
    Warning: Always shut down the Xserve before opening it to avoid damaging its internal components or the components you want to install. Don't open the Xserve or try to install items inside while it is turned on. Even after you shut down the Xserve, its internal components can be very hot. Let it cool down before you open it.
  2. If the Xserve case is locked, use the enclosure key to unlock the security lock on the front panel.
  3. Unplug all cables from the Xserve.

    Note: If you have trouble releasing a cable from the back panel, try using a small screwdriver or other flat tool to depress the tab on the cable connector.
  4. Loosen the thumbscrews at both ends of the front panel.
  5. Grasp the thumbscrews and pull the Xserve forward until the safety latches engage (about halfway out of the rack).

    Slide the Xserve forward
  6. When the safety latches engage, grip the Xserve where it emerges from the rack, press down on the latch tabs with your thumbs, and slide the Xserve the rest of the way out of the rack rails. Set the Xserve on a flat surface.
  7. Loosen the thumbscrews at the back of the top cover and slide the cover back and up to remove it. If you have difficulty removing the cover, check the enclosure lock on the front panel.

    Important: To minimize the possibility of damage to Xserve components due to static discharge, wear an antistatic wrist strap while you work inside the Xserve.

    Lift the back cover off

Step 2: Install the memory

  1. Open the ejectors on a slot by pushing them outward.

    Important: Don't touch the gold connectors on the DIMMs.
  2. Without touching its gold connectors, align a DIMM in the slot and push straight down on both ends until the DIMM is seated and the ejectors snap upright.
  3. Repeat for additional DIMMs.

    Slide memory into the slots

Step 3: Close the Xserve

  1. When you're finished working inside the Xserve, replace and secure the cover.
  2. Slide the Xserve back into the rack, and tighten the front thumbscrews to secure the Xserve in the rack.
  3. If the server case was locked, use the enclosure key to lock the security lock on the front panel.

Back to top


Applicable models

Xserve (Early 2008)
Xserve (Late 2006)

Memory specifications

These Xserve models have the following memory specifications:

Number of memory slots 8
Base memory 1 GB (two fully-buffered dual inline memory modules, FB, DIMMs)
Maximum memory 32 GB
Memory card specifications - 667 MHz DDR2 ECC FB-DIMMs
- 512 MB, 1 GB, 2 GB, or 4 GB in matching pairs (optimal, 4 or 8 identical DIMMs)
- 36 devices per DIMM, maximum
- Error-correcting code (ECC)
Additional notes Important: Apple recommends that you use Apple-approved DIMMs. Other DIMMs might degrade the performance of the Xserve. DIMMs from older Xserve systems are not compatible with this Xserve. You can purchase Apple-approved memory online from the Apple Store at www.apple.com/store.


The eight memory slots are labeled DIMM 1 through DIMM 8.

8 memory slots

You must install DIMMs in pairs, and the DIMMs in each pair must be identical (for example, the same size and speed). Install the first pair in slots 1 and 2. Install the next pair in slots 3 and 4. Install subsequent pairs in slots 5 and 6, then slots 7 and 8.

For the best performance, use identical DIMMs in all slots and fill up slots 1 through 4 before you install DIMMs in slots 5 through 8. If you don't have eight identical DIMMs, install identical DIMMs in slots 1 through 4 and a second set of four identical DIMMs in slots 5 through 8. If you can, after you fill slots 1 through 4, add a full set of four DIMMs in slots 5 through 8 instead of just a pair in slots 5 and 6.

Sample DIMM slots

Removing or installing memory

Step 1: Open the Xserve

  1. Shut down the Xserve and then wait a few minutes to let the Xserve internal components cool.
    Warning: Always shut down the Xserve before opening it to avoid damaging its internal components or the components you want to install. Don't open the Xserve or try to install items inside while it is turned on. Even after you shut down the Xserve, its internal components can be very warm. Let it cool down before you open it.
  2. If the Xserve case is locked, use the enclosure key to unlock the security lock on the front panel.
  3. Unplug all cables from the Xserve. If you have trouble releasing a cable from the back panel, try using a small screwdriver or other flat tool to depress the tab on the cable connector.
  4. Touch the server's metal case to discharge any static electricity.
  5. Loosen the thumbscrews at both ends of the front panel.
  6. Grasp the thumbscrews and pull the Xserve forward until the safety latches engage (about halfway out of the rack).

    Xserve in its rack
  7. When the safety latches engage, grip the Xserve where it emerges from the rack, press down on the latch tabs with your thumbs, and slide the Xserve the rest of the way out of the rack rails. Set the Xserve on a flat surface.
  8. Loosen the thumbscrews at the back of the top cover and slide the cover back and up to remove it. If you have difficulty removing the cover, check the enclosure lock on the front panel.
    Important: To minimize the possibility of damage to Xserve components due to static discharge, wear an antistatic wrist strap while you work inside the Xserve.

    Lift off the back cover

Step 2: Remove the installed memory

  1. Push down the ejectors on the FB-DIMM slot.
  2. Holding the FB-DIMM by both top corners, lift it straight up out of the Xserve.
    Warning: When removing or installing the DIMM, handle it only by the edges. Do not touch its connectors. Lift the DIMM straight up from the connector to remove it, and insert it straight down into the connector to install it. Do not rock the DIMM from side to side.

    Remove existing memory

Step 3: Install the replacement memory

  1. Position the replacement FB-DIMM over the memory slot.
    Note: The FB-DIMM is designed to fit into the slot only one way. Be sure to align the notch in the FB-DIMM with the small rib inside the slot.
  2. Without touching its gold connectors, align a DIMM in the slot and push straight down on both ends until the DIMM is seated and the ejectors snap upright.
  3. Repeat for additional DIMMs.

    Install new memory

Step 3: Close the Xserve

  1. When you're finished working inside the Xserve, replace and secure the cover.
  2. Slide the Xserve back into the rack, and tighten the front thumbscrews to secure the Xserve in the rack.
  3. If the server case was locked, use the enclosure key to lock the security lock on the front panel.

Back to top

Checking that your computer recognizes the new memory

When you restart the Xserve, watch for the Memory Slot Utility's evaluation of your new memory configuration.

Purchasing memory

Before you purchase DIMMs other than those recommended by Apple, make sure that the memory manufacturer conforms to the Joint Electron Device Engineering Council (JEDEC) specification. Make sure that the DIMMs support the correct timing modes and that the Serial Presence Detect (SPD) feature has been implemented in accordance with the JEDEC specification. To check DIMM compatibility, see the Macintosh Products Guide on Apple's website at www.apple.com/guide.

Important: Information about products not manufactured by Apple is provided for information purposes only and does not constitute Apple’s recommendation or endorsement. Please contact the vendor for additional information.
Last Modified: