Lenovo ThinkCentre M75s Gen 2 Small Form Factor upgrade guide

Updated Oct. 18, 2026 · Written from this device's verified specifications

The ThinkCentre M75s Gen 2 Small Form Factor is a friendly machine to upgrade: the memory is socketed (nothing is soldered down), the storage is standard SATA or M.2, and the processor sits in a regular AM4 socket. This guide covers what fits, the limits you need to respect, and what to watch out for before ordering parts. A quick note before you start: Lenovo lists this model under more than one machine type, and some of the exact limits below are not fully confirmed in Lenovo's documentation. Where that's the case, we say so - check the PSREF sheet and the Hardware Maintenance Manual (HMM) for your specific unit before buying. You can find the machine type on the label on your case and match it to Lenovo's PSREF page.

At a glance

  • Memory: 2 DDR4 UDIMM slots, DDR4-3200, non-ECC only
  • Storage: 3.5-inch/2.5-inch SATA bay plus an M.2 2280 slot (SATA or NVMe)
  • CPU: socketed AM4, Ryzen 5000 PRO, 65W maximum
  • Exact limits on memory totals and drive bay thickness are not fully confirmed - verify before buying
2x DDR4-3200 UDIMM (up to 32GB each)2 × DDR4 DIMM · up to 128 GB total · 3200 MT/s
3.5"/2.5" bays + M.2 2280 slot (SATA/NVMe)SSD / HDD 3.5" / 2.5" / M.2 2280 (SATA / NVMe)
AM4 socket (Ryzen 5000 PRO, 65W)AM4 · Ryzen 5000 · max 65 W
CPU · AM4max 65 W2 × DIMM · DDR4up to 128 GB total3.5"/2.5" bays + M.2 2280 slot(SATA/NVMe)SSD / HDD 3.5" / 2.5" / M.2 2280 (SATA /NVMe)
Schematic of the upgradeable slots (not to scale). Check the owner's manual for their exact positions.

Lifecycle and support

A current model: sold new and supported.

20202021202220232024202520262027Today11 · Release · Dec. 1, 2020
Filled dots: dates published by the manufacturer. Hollow dots: estimates from third-party sources.
MilestoneDate
Release
First available to buy.		 Dec. 1, 2020 Estimate Shipping start date (出荷開始日) on Lenovo's Japanese product page for MTM 11JA0002JP; announcement was 2020-09-29 per third-party database (https://pcnight.com/desktop/lenovo-thinkcentre-m75s-gen-2/), which is not the release date.
Source ↗

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

Memory (RAM)

The M75s Gen 2 Small Form Factor has 2 DDR4 DIMM (UDIMM) slots. It takes standard non-ECC, unbuffered DDR4 desktop modules running at DDR4-3200. Registered/buffered (RDIMM) and ECC modules are not supported, so don't pay extra for server memory - it won't work here. Nothing is soldered to the board, so both slots are yours to fill.

Buying tips

  • Buy non-ECC unbuffered DDR4 UDIMMs rated for DDR4-3200
  • Matched pairs (two identical modules) are the easiest way to fill both slots
  • Don't buy ECC or registered server memory - it is not supported

Storage

There is one storage area with a few options: a 3.5-inch or 2.5-inch SATA drive bay (SATA 6Gb/s) plus an M.2 2280 slot that accepts either an NVMe or a SATA SSD. For a quick speed boost, an M.2 2280 NVMe SSD is the simple choice. For a bigger hard drive or a second SSD, use the SATA bay. Adding a drive to the bay may require a drive caddy or rails and SATA data and power cables - check what's included with your unit before ordering a bare drive.

Buying tips

  • Fastest option: an M.2 2280 NVMe SSD
  • Biggest option: a 3.5-inch SATA hard drive or a 2.5-inch SATA SSD in the bay
  • Check for caddy/rails and SATA cables before buying a bare bay drive

Processor (CPU)

The processor is socketed, so it can be replaced. It uses the AM4 socket and ships with Ryzen 3/5/7 PRO 5000 G-series APUs on Lenovo's BIOS support list. The thermal design is built around 65W processors, so only 65W chips (typically the G-series/APU models, non-X) are officially supported. A higher-wattage or non-listed CPU may fit physically, but Lenovo's BIOS may not support it - that's a risk, not a guaranteed upgrade. If you want a faster chip, stay within the Ryzen 5000 PRO range Lenovo documents for this machine.

Buying tips

  • Choose a 65W processor from Lenovo's supported list for this model
  • Be wary of higher-wattage X-series chips - the 65W thermal design and vendor BIOS may not support them
  • Confirm support for your exact machine type before buying

How to upgrade

Before you start

  • Back up anything you care about.
  • Shut down the machine, switch it off and unplug the power cable and all peripherals.
  • Ground yourself (touch the metal chassis or use an anti-static strap) before handling parts.
  • Open the case - the exact clips, screws and panels differ, so follow the owner's manual or HMM for your machine type for the precise disassembly steps.
  • Install the part, close the case and reconnect the cables.
  • Power on and check that the BIOS/firmware sees the new part before booting into your operating system.

Steps

  1. Upgrade outline
    1. Back up your data. 2. Power off, unplug and ground yourself. 3. Open the case (see the manual for your exact machine type). 4. Install the memory, drive or processor. 5. Close the case. 6. Power on and confirm the BIOS/firmware reports the new part correctly.
  2. Notes for specific upgrades
    For memory, note which slots are occupied before removing modules and keep the empty-slot order in mind when adding. For a SATA drive, make sure you have the caddy or rails and the SATA data and power cables to hand. For a CPU, use the supported list and 65W limit as your guide, and handle the chip by its edges. The HMM and user guide show the exact screw and latch locations for this model.

Good to know

  • Machine types for this model are listed inconsistently (11RA/11JB in some places, 11T4/11T5 in others). Match the label on your unit before buying.
  • Memory slot count, the exact maximum total memory, and the 2.5-inch bay thickness limit (7mm vs 9.5mm) were not confirmed against Lenovo's PSREF and HMM. Verify these for your machine type before ordering parts.
  • No manufacturer-documented capacity limit was found for the drive bays, but treat large drives as untested until confirmed in Lenovo's documentation.

Frequently asked questions

How much RAM can the ThinkCentre M75s Gen 2 SFF take?

It has 2 DDR4 UDIMM slots and Lenovo's specs list DDR4-3200 modules of up to 32GB each. However, the totals don't reconcile across the figures we found (with 2 slots, 2 x 32GB is 64GB, while a maximum total of 128GB is also quoted), and this detail wasn't verified against the PSREF and HMM. Check the PSREF sheet and HMM for your machine type before ordering large modules.

Does the M75s Gen 2 support ECC memory?

No. It uses standard non-ECC, unbuffered DDR4 UDIMMs. ECC and registered (RDIMM) modules are not supported.

Can I install an NVMe SSD?

Yes. The M.2 2280 slot accepts NVMe or SATA SSDs. A 2.5-inch or 3.5-inch SATA drive can also go in the drive bay - you may need a caddy or rails and SATA cables for that.

Can I upgrade the CPU to a faster Ryzen?

The CPU is socketed (AM4) and replaceable, but Lenovo's BIOS support list and the 65W thermal design limit what officially works. Only 65W Ryzen 5000 PRO (typically G-series/APU) processors are covered; other chips may fit but are unsupported.

Is any memory soldered?

No. Both memory slots are user-replaceable - nothing is soldered to the board.

Which machine type is my M75s Gen 2?

Lenovo lists this model under more than one machine type (11RA/11JB in some documentation, 11T4/11T5 in others). Check the label on your unit and match it to Lenovo's PSREF page so you buy parts and follow steps for the right configuration.

Official documents and references

This guide was written with AI assistance from the compatibility data PartsPrices verified against the manufacturer's documents. Always check your exact model and the owner's manual before buying or opening your computer.