Dell OptiPlex 7090 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.

Memory (RAM)

The OptiPlex 7090 Micro has two socketed DDR4 SO-DIMM slots (260-pin) and no soldered memory, so both slots are yours to use. The maximum is 32 GB per module and 64 GB in total (2 x 32 GB).

Memory type matters. You need DDR4 SO-DIMMs (laptop-style modules), non-ECC and unbuffered. ECC and registered (RDIMM) memory is not supported by the Q570 platform, despite the machine's business pedigree.

Speed is determined by the processor you have, not by what you buy. With a 10th-gen i5, memory runs at 2666 MT/s; with a 10th-gen i7 or i9, at 2933 MT/s; with any 11th-gen chip, at 3200 MT/s. Faster modules simply clock down to those rates, so there is no point paying a premium for DDR4-3200 unless you plan to fit an 11th-gen CPU later.

For the best performance, install memory in matched pairs so the machine runs in dual-channel mode. Dell's valid configurations run from 1 x 4 GB up to 2 x 32 GB.

Buying tip: pick a matched kit of two modules at the speed your CPU can actually use. Kingston's compatibility list is a handy cross-check, and non-ECC unbuffered DDR4-3200 modules will run happily at lower speeds in 10th-gen systems.

Buying tips

• Buy a matched pair (2 x 8 GB, 2 x 16 GB or 2 x 32 GB) for dual-channel performance
• Choose the speed your CPU supports — 2666, 2933 or 3200 MT/s — to avoid paying for speed you cannot use
• Avoid ECC and registered modules; this machine only takes non-ECC unbuffered SO-DIMMs

Storage (M.2 SSDs and the 2.5-inch bay)

There are two M.2 M-key slots for NVMe SSDs, and they accept both 2230 and 2280 drives according to Dell's Technical Guidebook. Dell's own product page describes the slots slightly differently — one 2230/2280 and one 2280 only — so if you want a short 2230 drive, open the case and check the second slot's standoff position before buying. Intel Optane H10 drives are supported.

Speed and generation depend on your CPU. With a 10th-gen processor the M.2 slots run at PCIe Gen3 x4; Gen4 x4 is available only with an 11th-gen CPU. A Gen4 drive will still work in a 10th-gen system, but it will run at Gen3 speeds.

2 TB is the largest SSD Dell offered (a Class 40 2280 drive), but that reflects Dell's sales catalogue rather than a hard technical limit. In SSD configurations, the first M.2 drive is normally the boot device.

On integrated-graphics models there is also one 2.5-inch SATA 3.0 bay (up to 6 Gb/s) for a hard drive or SSD. Drives of 7 mm to 9 mm fit; 9.5 mm drives are not confirmed. Note that discrete-graphics (DGFX) SKUs do not have this bay at all, so if a secondary 2.5-inch drive matters to you, buy the integrated-graphics model.

Dell's catalogue shows 2.5-inch drives topping out at 2 TB (HDD) or 500 GB (SSD), but again those are the options Dell sold, not a technical ceiling. There are no 3.5-inch bays, no optical drive and no memory card reader, and no PCIe add-in card slots. The riser connector on the board exists only for Dell's optional legacy serial/VGA module.

Buying tip: for the main drive, a 2280 NVMe SSD is the safe choice in either slot. Only choose a 2230 drive if you have confirmed the standoff for it, and only plan on a 2.5-inch drive if your machine is the integrated-graphics version.

Buying tips

• Prefer a 2280 NVMe SSD — it fits both slots regardless of which version of the slot layout you have
• Don't pay extra for Gen4 unless you have an 11th-gen CPU; 10th-gen systems run M.2 at Gen3 x4
• Check your model is not a DGFX (discrete-graphics) SKU before buying a 2.5-inch drive — those have no SATA bay

Processor (CPU)

The processor sits in a removable LGA1200 socket on a Q570 board, so it can be replaced. Supported chips are 10th-gen Intel Core i3/i5/i7/i9 (Comet Lake, plus Celeron/Pentium models) and 11th-gen Core i5/i7/i9 (Rocket Lake). 11th-gen is the ceiling — 12th and 13th-gen processors are not supported.

On power, Dell's processor table lists both 35 W T-series and 65 W parts, and 65 W is the platform ceiling. However, most Micro configurations shipped with 35 W T-series chips (for example the i7-10700T), and the tiny chassis and cooling are designed around them. If you want a quiet, safe upgrade, a 35 W T-series chip is the sensible route.

One more caveat: the supported CPU list depends on your machine's BIOS and microcode version (for example 11JN versus 0A36), so check your exact service tag on Dell's support site before ordering a processor. What worked for someone else's 7090 Micro may not be listed for yours.

Buying tip: identify your current CPU and service tag first, then pick a 10th or 11th-gen chip from the list Dell publishes for your machine. A used T-series i7 or an 11th-gen upgrade gives you both more cores and faster memory and storage support.

Buying tips

• Look up your service tag on Dell's support site to see the CPU list for your BIOS version
• Stay with 35 W T-series chips; the Micro chassis is built around them
• Moving to an 11th-gen CPU unlocks DDR4-3200 memory speed and Gen4 NVMe support

How to upgrade

Before you start

• Back up your data first — upgrades can go wrong and drives can fail during cloning or migration.
• Shut down the machine and unplug the power cable and all connected devices.
• Ground yourself (touch a metal part of the chassis) to avoid static damage to the components.
• Open the case and install the part. Dell's owner's and service manuals show the exact disassembly steps for the Micro chassis, including any release latches or screws, so keep them to hand.
• Close the case, reconnect power and start the machine, then check that the BIOS and firmware see the new part at the expected capacity or speed.

Steps

1. 1. Back up your data
   Back up anything important before you open the case. If you are replacing the boot drive, plan how you will move Windows and your files to the new SSD first.
2. 2. Power off and unplug
   Shut the system down fully and unplug the power cable and all peripherals. Never work on a machine that is still connected to mains power.
3. 3. Ground yourself
   Touch a metal part of the chassis to discharge static, or use an anti-static strap. Memory modules and SSDs are easy to damage with static.
4. 4. Open the case and install
   Open the Micro chassis and fit the part — push SO-DIMMs firmly into their slots, seat M.2 drives in the connector and secure them at the standoff, and handle the processor by its edges. Dell's owner's and service manuals describe the exact disassembly for this model, including any release latches or screws, so follow them rather than forcing anything.
5. 5. Close the case
   Refit the cover and any screws, then reconnect the power cable and your devices.
6. 6. Check the BIOS and firmware
   Start the machine and enter the BIOS to confirm the new memory or drive is detected at the expected size. For a CPU upgrade, confirm the model is reported correctly, and make sure your BIOS is up to date for your service tag.

Good to know

• Dell's documents describe the two M.2 slots differently: the Technical Guidebook says both take 2230/2280 drives, while Dell's product page says one 2230/2280 and one 2280. Check the second standoff before buying a 2230 drive.
• Dell's manuals disagree about storage limits in places; sizes such as 2 TB (HDD) and 500 GB (SATA SSD) reflect what Dell sold rather than confirmed technical limits.
• Sources do not confirm that 9.5 mm 2.5-inch drives fit; 7 mm and 9 mm drives are confirmed.

Frequently asked questions

How much RAM can the Dell OptiPlex 7090 Micro take?

Up to 64 GB, using two 32 GB DDR4 SO-DIMM modules (one per slot). There is no soldered memory, so both slots are available. Memory must be non-ECC and unbuffered.

Does the OptiPlex 7090 Micro support DDR5?

No. It takes DDR4 SO-DIMMs only. It also does not support ECC or registered memory, and it runs at 2666, 2933 or 3200 MT/s depending on which CPU is installed.

How many SSDs can I install?

Two M.2 NVMe SSDs, plus a 2.5-inch SATA drive if you have the integrated-graphics model. The discrete-graphics (DGFX) versions have no 2.5-inch bay.

Does it support PCIe Gen4 NVMe drives?

Only with an 11th-gen processor. With a 10th-gen CPU the M.2 slots run at PCIe Gen3 x4. Gen4 drives still work in 10th-gen systems, but at Gen3 speeds.

Can I upgrade the CPU in the OptiPlex 7090 Micro?

Yes. The socketed LGA1200 processor supports 10th-gen (i3/i5/i7/i9, Celeron/Pentium) and 11th-gen (i5/i7/i9) Intel Core chips. 11th-gen is the ceiling — 12th and 13th-gen CPUs are not supported — and the supported list depends on your BIOS version, so check your service tag on Dell's support site first.

What size 2.5-inch drive fits?

Drives 7 mm to 9 mm thick are confirmed to fit the SATA bay. 9.5 mm drives are not confirmed, so stick to 7 mm or 9 mm drives.

Official documents and references

• PDF Dell OptiPlex 7090 Technical Guidebook / product catalogue (PDF)
  Main source for memory configurations, storage options, processor list and the DGFX SKU note.
• Dell OptiPlex 7090 Micro Setup and Specifications manual
  Official Dell manual covering ports, slots and setup for the Micro model.
• PDF Dell OptiPlex 7090 Micro service and safety notes (PDF)
  Useful alongside the owner's manual for disassembly and safety guidance.
• PDF Dell OptiPlex 7090 Micro Statement of Volatility (PDF)
  Confirms the socketed DDR4 memory at DIMM1/DIMM2.
• Dell OptiPlex 7090 Micro product page
  Dell's description of the M.2 slot layout and the missing SATA bay on DGFX models.
• Kingston memory compatibility list for the Dell OptiPlex 7090 Micro
  Handy cross-check for compatible DDR4 SO-DIMM part numbers and specs.