Dell OptiPlex 7070 SFF Upgrade Guide: RAM, SSD and CPU

Lifecycle and support

A current model: sold new and supported.

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

RAM: up to 64 GB of DDR4 UDIMM

The OptiPlex 7070 SFF has four slots for full-size DDR4 desktop modules (UDIMM, not laptop SO-DIMM). Each slot takes up to 16 GB, for a maximum of 64 GB. The minimum is 4 GB. Dell lists these configurations: 1x4, 1x8, 2x4, 1x16, 2x8, 2x16, 4x8 and 4x16 GB.

Modules are rated for 2666 MHz. On Core i3 processors they run at 2400 MHz instead, so faster RAM won't help there. Only non-ECC memory is supported; Dell lists no ECC or registered support.

One of Dell's service manuals says the memory is embedded in the board and not replaceable. That is generic text that contradicts Dell's own specifications and the same manual's module removal steps. The memory is socketed and upgradable.

Buying tips

• Buy DDR4 UDIMM (full-size desktop) modules, not SO-DIMM
• Choose non-ECC, unbuffered modules only
• On a Core i3 model, 2666 MHz modules will run at 2400 MHz, so don't pay extra for speed
• Stick to a configuration Dell lists, for example 2x8 GB or 2x16 GB

Storage: M.2 SSD, 2.5 inch drives or a 3.5 inch drive

There is one M.2 slot for a 2280-length SSD. It accepts either a PCIe 3.0 x4 NVMe drive or a SATA M.2 drive. The SSD is held by a single M2x3.5 screw and sits on a thermal pad.

The drive bays are an either/or choice: the chassis takes two 2.5 inch SATA drives (one on each side of the bracket, HDD or SSD) or one 3.5 inch SATA HDD, not both. Dell lists up to 2 TB for SSDs and HDDs. Dell's documents don't give a thickness limit for 2.5 inch drives, so check this before fitting a thick drive.

Permitted combinations are: M.2 alone, M.2 plus one 2.5 inch or one 3.5 inch drive, one or two 2.5 inch drives, or one 3.5 inch drive alone. Your unit may not include the cage, bracket or cabling for the bay layout you want. A slimline optical drive, if fitted, also uses a SATA connection.

An optional Intel Optane module uses the same M.2 slot, so it can't be fitted alongside an M.2 SSD. Optane only accelerates storage and does not add RAM. Dell's documents disagree on its capacity (16 GB in the specifications, 32 GB in the service manual).

Buying tips

• For the fastest drive, buy a 2280 NVMe SSD (PCIe 3.0 x4); a SATA M.2 2280 SSD also works
• Make sure the M.2 drive is 2280 length, not 2230 or 2242
• Choose 2.5 inch SATA SSDs for the bays if you want two drives; a 3.5 inch drive rules out a second 2.5 inch one
• Check your unit has the bracket or cage for your chosen layout before buying
• Don't plan on Optane and an M.2 SSD together; there is only one M.2 slot

CPU: socketed, but check compatibility first

The processor is socketed, with a socket lever, a processor shield and a separate heat sink assembly, so it can be replaced. Dell's documents we checked don't name the socket, the supported generations or the maximum power rating. These CPUs use LGA1151, with 8th and 9th generation Core processors and a 65 W limit, but treat that as unconfirmed.

Before buying, confirm the exact processor on Dell's processor specification page for the OptiPlex 7070. A BIOS update may be needed for a newer CPU to be recognised.

Buying tips

• Confirm the exact CPU model on Dell's processor page before buying
• Stay at or below 65 W for this small chassis
• Look for a processor from the 8th or 9th generation Core family only
• Update the BIOS before swapping the CPU if Dell's page says it is needed
• Remember that a Core i3 limits RAM to 2400 MHz

How to upgrade

Before you start

• Back up your important files and note your Windows licence and any BitLocker recovery keys
• Check which options your unit has: 3.5 inch or dual 2.5 inch bracket, optical drive, SD reader, Optane
• Note your current CPU model and BIOS version
• Keep the owner's manual or Dell service manual handy for exact disassembly steps
• Have a small screwdriver ready; an M.2 SSD needs an M2x3.5 screw

Steps

1. Back up and prepare
   Back up your data, and if you plan a CPU change, update the BIOS first if Dell's processor page says it is required.
2. Power off and unplug
   Shut the computer down fully, unplug the power cable and any other cables, then hold the power button for a few seconds to discharge residual power.
3. Ground yourself
   Work on a clean, flat surface and touch bare metal on the chassis before handling parts. Hold components by their edges.
4. Open the case
   Remove the cover following the owner's manual or Dell service manual for exact disassembly. Remove the drive bracket or heat sink only if the job needs it.
5. Install the part
   For RAM, open the retention tabs on the slot, seat the module firmly and let the tabs click back. For an M.2 SSD, slide it into the slot, place the thermal pad as the manual shows and secure it with the M2x3.5 screw. For 2.5 inch or 3.5 inch drives, fit them in the bracket as the manual describes. For a CPU, follow the service manual's socket lever, processor shield and heat sink procedure.
6. Close up and reconnect
   Refit any brackets and the cover, then reconnect the cables and power.
7. Check the BIOS
   Power on and open the BIOS setup. Confirm the new memory total, drive or processor is listed. For a new drive, you will then need to install or clone an operating system.

Good to know

• Dell's documents don't name the CPU socket, supported generations or power limit; the LGA1151, 8th/9th gen and 65 W details are unconfirmed, so verify on Dell's processor page before buying.
• Dell's documents disagree on Optane capacity: 16 GB in the specifications, 32 GB in the service manual.
• One service manual says memory is embedded; this contradicts Dell's specifications and should be ignored.
• Dell doesn't state a thickness limit for 2.5 inch drives, so check before fitting thick drives.
• Optional hardware varies by unit: the 3.5 inch or dual 2.5 inch bracket, optical drive, SD reader, Optane and the self-encrypting drive may not be present on yours.

Frequently asked questions

How much RAM can the Dell OptiPlex 7070 SFF take?

Up to 64 GB, using four 16 GB DDR4 UDIMMs. The minimum is 4 GB. Modules run at 2666 MHz, or 2400 MHz on Core i3 processors.

Does the OptiPlex 7070 SFF use laptop SO-DIMM or ECC memory?

No. It takes full-size desktop UDIMMs, and only non-ECC. Dell lists no ECC or registered support.

Can I install an NVMe SSD in the OptiPlex 7070 SFF?

Yes. The single M.2 slot takes a 2280 PCIe 3.0 x4 NVMe SSD, and it also accepts a SATA M.2 2280 SSD.

Can I fit a 3.5 inch drive and two 2.5 inch drives together?

No. The chassis takes either one 3.5 inch drive or two 2.5 inch drives. You can add an M.2 SSD alongside either layout.

Can I use Intel Optane and an M.2 SSD together?

No. An optional Optane module uses the same M.2 slot as an M.2 SSD, so you can only fit one of them.

Can I upgrade the processor in the OptiPlex 7070 SFF?

The CPU is socketed, so it can be replaced. Dell's documents we checked don't name the socket or list supported processors; these CPUs use LGA1151 (8th and 9th gen Core, up to 65 W). Verify on Dell's processor page first, and a BIOS update may be needed.

Official documents and references

• PDF Dell OptiPlex 7070 Small Form Factor Setup and Specifications (PDF)
  Full official specification sheet
• Dell OptiPlex 7070 SFF memory specifications
  Slots, capacity, speed and supported configurations
• Dell OptiPlex 7070 SFF storage specifications
  M.2, 2.5 inch and 3.5 inch drive details
• Dell OptiPlex 7070 SFF storage combinations
  Which drive combinations are permitted
• Dell service manual: installing the hard drive
  Official drive installation steps
• PDF OptiPlex 7070 SFF service manual (PDF, third-party host)
  Removal and installation steps for memory, M.2 SSD and processor