Dell PowerEdge R240 Upgrade Guide: RAM, Storage and CPU

Lifecycle and support

No longer sold new. Supported until March 31, 2027 (estimate).

Dates not listed haven't been published by the manufacturer or a reliable third party.

RAM: ECC UDIMMs, up to 64 GB

The R240 has four 288-pin DIMM sockets running DDR4 at 1.2 V. Dell lists 8 GB and 16 GB modules, single or dual rank, and nothing larger. The minimum is 8 GB, and the maximum is 32 GB with 8 GB modules or 64 GB with 16 GB modules. Dell lists no 32 GB modules, so we can't confirm that more than 64 GB works.

The memory must be unbuffered ECC (ECC UDIMM). Dell's documents disagree on this: the spec sheet and the India product page say 'registered ECC', but they also say UDIMM, and the technical guide and manuals consistently describe unbuffered ECC only. Treat 'registered' as a wording slip and buy ECC UDIMMs, not RDIMMs or LRDIMMs. Don't assume non-ECC modules will work.

The system has two memory channels. Channel 0 uses slots A1 and A3, and channel 1 uses A2 and A4. The first socket in each channel is white and the second is black. Speed tops out at 2666 MT/s with one or two DIMMs per channel. 3200 MT/s UDIMMs are compatible from BIOS 2.5.1 but run at 2666 MT/s. Dell also notes that memory off-lining is not supported.

Buying tips

• Search for 'DDR4 ECC UDIMM', 8 GB or 16 GB, and avoid anything labeled RDIMM, LRDIMM or SO-DIMM.
• Buy matching modules in pairs so each channel is filled evenly.
• Faster 3200 MT/s modules gain nothing here and need BIOS 2.5.1 or later, so 2666 MT/s is the sensible choice.
• Don't pay extra for modules above 16 GB. Dell lists nothing larger.

Storage: front bays, boot options and PCIe cards

The R240 has no onboard M.2 or NVMe slot. Drives go in the front bays, and the chassis is fixed when the server is ordered: 2 or 4 bays, cabled or hot-plug. Cabled bays take 3.5" SATA or Nearline SAS drives. The hot-plug chassis takes SATA, Nearline SAS, SAS and SSDs. Dell's technical guide says SSDs are only available in hot-plug configurations. Dell's spec sheet is looser and mentions SSDs for cabled bays, so plan on hot-plug if you want an SSD. 2.5" drives need 3.5" carriers. Dell gives no 2.5" thickness limit.

Maximum capacity is listed as 56 TB for the 4-bay configurations and 28 TB for the 2-bay cabled one. Internal controller options are the PERC H330, PERC H730P and HBA330, with PERC S140 for software RAID and a 12 Gb SAS external HBA.

Two boot-only options exist. The optional BOSS card carries one or two fixed 240 GB M.2 drives (RAID 1 or no RAID with two, no RAID with one). It uses one of the two PCIe slots, isn't hot-plug, and isn't a general M.2 upgrade. Dell doesn't say whether those modules are SATA or NVMe, so don't assume NVMe. The optional Internal Dual SD Module takes one or two microSD cards of 16, 32 or 64 GB, intended for a hypervisor or boot.

If you want an add-in storage card, slot 1 is low-profile, half-length PCIe Gen3 with x4 lanes. Slot 2 is full-height or low-profile, half-length PCIe Gen3 with x8 lanes. Maximum card length is 167.65 mm. Dell's documents describe the slot widths inconsistently (x8 and x16 connectors versus x4 and x8 lanes), so expect x4 and x8 electrical lanes.

Buying tips

• Check whether your server has 2 or 4 bays and whether they are cabled or hot-plug before buying any drive.
• Cabled chassis: stick to 3.5" SATA or Nearline SAS HDDs.
• For an SSD, you need the hot-plug chassis. A 2.5" SSD also needs a 3.5" carrier.
• Don't buy a general M.2 or NVMe adapter expecting it to be supported. Dell lists none.
• A BOSS card or any other storage card uses one of only two PCIe slots.

CPU: LGA1151 Xeon, Core i3, Pentium or Celeron

The R240 has a single LGA1151 socket on the Intel C246 chipset. Dell lists Xeon E-2100 and E-2200 processors, plus Core i3-8100 and i3-9100, Pentium G5500 and G5420, and Celeron G4900 and G4930. Dell's documents don't list Xeon E-2300 parts, so don't buy one expecting it to work.

The highest power rating in Dell's processor table is 95 W (the E-2288G and E-2286G). That table looks like a general family list rather than a statement of what Dell sold, and it flags some parts as not supported. Check any specific CPU with Dell, using its configurator or BIOS release notes, before you buy.

Integrated graphics can't be used, even on 'G' models. Video comes from the Matrox G200 in iDRAC9. Dell's documents also don't say whether ECC memory works with every CPU in the list, so confirm that for your chosen part, especially the Core i3, Pentium and Celeron options.

Buying tips

• Buy only a model number that Dell names. Don't rely on 'LGA1151' alone, since other LGA1151 chips won't be supported.
• Stay at or under 95 W, and confirm the exact part with Dell first.
• Don't pay extra for integrated graphics. They can't be used in this server.
• Keep your power supply in mind. It is a single 250 W (Bronze) or 450 W (Platinum) unit.

How to upgrade

Before you start

• Find your chassis type (2 or 4 bays, cabled or hot-plug) and your power supply rating.
• Download the owner's manual (Installation and Service Manual) for exact disassembly and part locations.
• Check that your BIOS and iDRAC firmware are up to date. BIOS 2.5.1 or later is needed for 3200 MT/s modules, which run at 2666 MT/s anyway.
• Back up everything you care about, especially if you plan to change drives or RAID setups.
• Have an anti-static wrist strap or a grounded surface ready.

Steps

1. Back up your data
   Make a full backup of the server and note your RAID and BIOS settings before touching any hardware.
2. Power off and unplug
   Shut the server down properly, then disconnect the power cord(s) and any other cables. Wait for it to fully power down.
3. Ground yourself
   Use an anti-static strap or touch bare metal on the chassis before handling parts. Hold memory modules and CPUs by their edges.
4. Open the case
   Open the server following the owner's manual. It shows the exact procedure for removing covers and any shrouds.
5. Install the new part
   For RAM, fit ECC UDIMMs in the sockets. Channel 0 uses A1 and A3, channel 1 uses A2 and A4, and the first socket in each channel is white. For drives, use the correct bay and carrier for your chassis, with 2.5" drives in 3.5" carriers. For a CPU or PCIe card, follow the manual's steps. Don't force anything.
6. Close and reconnect
   Refit all covers and shrouds, then reconnect the cables and power.
7. Check that the system sees it
   Power on and enter the BIOS or iDRAC to confirm the new memory, drive or CPU is detected. If it isn't, power down and re-check the seating and compatibility.

Good to know

• Dell's documents disagree on registered versus unbuffered memory. We recommend ECC UDIMMs based on the technical guide.
• Dell's documents disagree on whether cabled bays can take SSDs. The technical guide says SSDs are for hot-plug configurations only.
• Dell doesn't state the M.2 length, or whether the BOSS modules are SATA or NVMe.
• Dell gives no 2.5" drive thickness limit.
• PCIe slot widths are described inconsistently across Dell's documents. Expect x4 and x8 electrical lanes.
• The 95 W processor limit comes from a table that may be a general family list. Confirm any specific CPU with Dell before buying.
• Dell's documents don't say whether ECC works with every supported CPU option.
• This guide can't confirm memory above 64 GB or modules other than 8 GB and 16 GB.

Frequently asked questions

How much RAM can the Dell PowerEdge R240 take?

Up to 64 GB, using four 16 GB ECC UDIMMs. With 8 GB modules the maximum is 32 GB, and the minimum is 8 GB. Dell lists nothing larger than 16 GB per module.

Does the R240 use registered or unbuffered memory?

Dell's documents disagree. Some pages say 'registered ECC', but the technical guide specifies unbuffered ECC, and those pages also say UDIMM. Buy ECC UDIMMs and avoid RDIMMs.

Can I use 3200 MT/s RAM in an R240?

Dell says 3200 MT/s UDIMMs are compatible from BIOS 2.5.1, but they run at 2666 MT/s, which is the maximum speed for this server.

Does the R240 support NVMe or M.2 SSDs?

There is no onboard M.2 or NVMe slot. The optional BOSS card holds fixed 240 GB M.2 boot drives. It uses a PCIe slot and isn't a general M.2 upgrade, and Dell doesn't say whether those modules are SATA or NVMe.

Can I put an SSD in my R240?

Dell says SSDs are only available in the hot-plug configurations, and 2.5" drives need 3.5" carriers. Cabled-bay models take SATA or Nearline SAS drives. Dell's spec sheet is less clear on this, so check your chassis first.

What CPUs does the R240 support?

The LGA1151 socket takes Xeon E-2100 and E-2200 processors, Core i3-8100 and i3-9100, Pentium G5500 and G5420, and Celeron G4900 and G4930. The highest power rating in Dell's table is 95 W, so confirm any specific CPU with Dell before buying.

Official documents and references

• PDF Dell PowerEdge R240 Technical Guide
  Memory, drive bay, BOSS, PCIe slot and processor details
• PDF Dell PowerEdge R240 Spec Sheet
  Controllers, IDSDM, power supplies and processor families
• Dell PowerEdge R240 Technical Specifications: Memory
  Supported module sizes, minimum and maximum memory
• Dell PowerEdge R240 System Memory Guidelines
  Channel layout, socket colors and memory speed
• Dell PowerEdge R240 Expansion Card Installation Guidelines
  PCIe slot guidance for add-in cards
• PDF Dell Server Generation Comparison Matrix: R240
  Maximum drive capacity by configuration
• PDF Dell EMC PowerEdge R240 Installation and Service Manual
  Owner's manual for exact disassembly and installation steps (third-party hosted copy)