Dell OptiPlex 3070 Micro 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: two SODIMM slots, up to 32 GB

The Micro has two SODIMM slots, one module per channel. It takes non-ECC, unbuffered DDR4 SODIMMs only. Full-size desktop DIMMs do not fit. Each module can be up to 16 GB, so the maximum is 32 GB (2 x 16 GB). Dell's listed configurations run from 4 GB (1 x 4 GB) up to 32 GB, including 8 GB (1 x 8 GB or 2 x 4 GB) and 16 GB (1 x 16 GB or 2 x 8 GB).

Speed depends on your processor. Memory runs at DDR4-2666 (2666 MT/s) with Core i5 and i7 chips, but at 2400 MT/s with Celeron, Pentium and Core i3 chips. Faster modules won't go beyond those speeds.

One line in a Dell service manual says the memory is embedded in the board and not replaceable. That contradicts Dell's specification tables, which describe two SODIMM slots and no soldered memory. We can't confirm why the manuals differ, so check your own unit when you open the case, and look at your service tag before buying.

Buying tips

• Buy DDR4 SODIMM (laptop-size), non-ECC. Not desktop DIMMs.
• Two matching modules, such as 2 x 8 GB, are a sensible way to reach 16 GB.
• Modules rated above 2666 MT/s won't run faster than 2666, and with a Celeron, Pentium or i3 the limit is 2400.
• Don't exceed 16 GB per module.

Storage: one M.2 slot and one 2.5-inch bay

The Micro has one M.2 SSD slot that accepts SATA or NVMe drives, and one 2.5-inch SATA bay for a hard drive or SSD. It has no 3.5-inch bay. A second M.2 slot exists, but it is for the Wi-Fi/Bluetooth card and can't be used for storage.

Dell's lists top out at 1 TB for M.2 SSDs and 2 TB for 2.5-inch drives. Neither is stated as a hard limit, and larger drives may work, but Dell doesn't list them. Dell's documents also don't say which PCIe generation the M.2 slot uses, what the maximum 2.5-inch drive thickness is, or which M.2 lengths fit. Only the Optane module is described as 2230/2280, so we can't confirm either length for ordinary SSDs.

A 2.5-inch SSD can only be used as a secondary drive, paired with an M.2 SSD as the primary. If you plan to use only the 2.5-inch bay, check this first.

Dell's manuals also list an Optane module for the M.2 slot, but they disagree on the capacity: 16 GB in one and 32 GB in another. Optane only accelerates a drive; it does not add RAM or usable storage.

Buying tips

• For the fastest boot drive, choose an M.2 SSD. Dell's list covers up to 1 TB.
• Check the length (2230 or 2280) before buying, because the M.2 length limits aren't documented.
• Choose a 2.5-inch SATA drive for extra bulk storage, up to the 2 TB Dell lists.
• Don't plan on a 3.5-inch drive or a PCIe card. Neither fits.

How to upgrade

Before you start

• Back up your files, or clone your current drive, before changing any storage.
• Check your service tag on Dell's support site to confirm your exact configuration, since Dell's manuals disagree on some points.
• Find out which processor you have, because it sets your memory speed.
• Have the owner's manual open for exact disassembly instructions.
• Prepare a small screwdriver and a clean, static-free workspace.

Steps

1. Back up and shut down
   Save your data, then shut Windows down completely rather than using sleep or hibernate.
2. Unplug everything
   Disconnect the power adapter and all cables from the Micro.
3. Ground yourself
   Touch bare metal on the case or wear an anti-static strap before handling any parts, and hold parts by their edges.
4. Open the case
   Follow the owner's manual for removing the cover and reaching the memory, M.2 slot and 2.5-inch bay on the Micro.
5. Install the new part
   For RAM, fit SODIMMs into the slots. For storage, fit the M.2 SSD in the SSD slot rather than the Wi-Fi slot, or install the 2.5-inch drive in its bay. Follow the manual for how each part is secured.
6. Close the case and reconnect
   Replace the cover, then reconnect the power and peripherals.
7. Check that the system sees it
   Open the BIOS setup screen at startup, or check system information in Windows, to confirm the new memory or drive shows up. A new blank drive will need an operating system installed or a cloned copy.

Good to know

• Dell's documents don't name the CPU socket or say whether the processor is user-replaceable. Confirm this before planning a CPU swap.
• Dell lists only 35 W T-series 8th and 9th gen chips for the Micro. The 65 W desktop parts are listed for the larger Tower and SFF models only.
• Dell marks its CPU lists as offered offline only, so the processor in your unit depends on how it was configured.
• A Celeron, Pentium or Core i3 runs memory at 2400 MT/s, not 2666 MT/s, so faster RAM won't help there.
• The Micro has no PCIe expansion slots and no 3.5-inch bay, so there is no graphics card upgrade path.
• Dell's manuals disagree on whether the RAM is soldered and on the Optane module capacity. Check your unit and service tag before buying parts.

Frequently asked questions

How much RAM can the OptiPlex 3070 Micro take?

Up to 32 GB, as two 16 GB DDR4 SODIMMs. Dell's smallest listed configuration is 4 GB.

Does the OptiPlex 3070 Micro use DDR4 or DDR3?

DDR4. It takes non-ECC, unbuffered SODIMMs. Desktop DIMMs do not fit.

Is the RAM soldered in the OptiPlex 3070 Micro?

Dell's specification tables list two SODIMM slots and no soldered memory. One service manual line says the memory is embedded, which contradicts them. Check your own unit when you open the case.

Can I add an NVMe SSD to the OptiPlex 3070 Micro?

Yes. The M.2 slot accepts SATA or NVMe SSDs, and Dell lists drives up to 1 TB. The PCIe generation isn't documented. The second M.2 slot is for Wi-Fi only.

Can I use both an M.2 SSD and a 2.5-inch drive?

Yes. Dell notes that a 2.5-inch SSD can only be a secondary drive, with an M.2 SSD as the primary.

Can I upgrade the CPU in the OptiPlex 3070 Micro?

This is unconfirmed. Dell lists only 35 W T-series 8th and 9th gen Intel processors for the Micro, such as the Core i7-9700T and i7-8700T, and its documents don't name the socket or say the CPU is user-replaceable. Check this before buying a processor.

Official documents and references

• Dell OptiPlex 3070 Micro: memory specifications
  Slot count, DDR4 type and supported memory sizes
• PDF OptiPlex 3070 user manual (PDF)
  Storage tables covering drive bays, M.2 slots and supported drives
• PDF OptiPlex 3070 Micro service manual (PDF)
  Disassembly guidance and Optane notes
• Dell OptiPlex 3070: processor specifications
  List of supported 35 W T-series CPUs