Dell OptiPlex 7040 Micro upgrades

Released 2015 · end of sale

Micro form factor with no 3.5" bay, no optical drive, no card reader and no RAID (MT/SFF siblings differ). Uses a 65 W external power brick - when buying used, confirm the adapter is included. 32 GB RAM and M.2 NVMe boot are well proven despite Dell's older 16 GB documentation.

Upgrade guide → What fits, step by step, and official documents.

2x DDR4 SO-DIMM (260-pin), non-ECC: 2 × DDR4 SO-DIMM · up to 32 GB total · 2133 MT/s
M.2 2280 Socket 3 (M-key) - SATA or NVMe: SSD M.2 2242 / M.2 2260 / M.2 2280 (SATA / NVMe)
2.5" SATA bay (6 Gbps): HDD / SSD 2.5" (SATA) · max 7 mm thick · up to 2 TB
LGA 1151 (Socket H4) - 35 W T-series only: LGA1151 (6th/7th gen) · Core 6th gen · max 35 W

Slot map

Schematic of the upgradeable slots (not to scale). Check the owner's manual for their exact positions.

2x DDR4 SO-DIMM (260-pin), non-ECC 2 × DDR4 SO-DIMM · up to 32 GB total · 2133 MT/s

Dell's original Owner's Manual caps 8 GB/slot (16 GB total), but Dell community, Kingston and MemoryCow validate 2x16 GB = 32 GB in practice. Only 2133 MT/s is native; faster DDR4 (2400-3200) will simply downclock. Use 2 matched non-ECC unbuffered SO-DIMMs for dual-channel (HD 530 graphics benefit). ECC modules will not work.

No compatible offers right now.

M.2 2280 Socket 3 (M-key) - SATA or NVMe SSD M.2 2242 / M.2 2260 / M.2 2280 (SATA / NVMe)

Socket 3 M-key supports both M.2 SATA and PCIe NVMe Gen3 x4 (~3.5 GB/s ceiling). Shorter 2242/2260 drives fit with the correct screw position; 22110 does not fit. Update BIOS and set the correct SATA operation mode before NVMe boot. The separate M.2 2230 slot is Wi-Fi/BT only, not storage.

No compatible offers right now.

2.5" SATA bay (6 Gbps) HDD / SSD 2.5" (SATA) · max 7 mm thick · up to 2 TB

Dell ships 7 mm drives in this bay; MemoryCow advertises 9.5 mm compatibility but 7 mm is the safe choice - verify against your caddy. Dell validated HDDs up to 2 TB; larger 2.5" SATA SSDs (4 TB+) physically work but are unvalidated. M.2 SSD + 2.5" drive can coexist. No RAID support on the Micro model.

No compatible offers right now.

LGA 1151 (Socket H4) - 35 W T-series only LGA1151 (6th/7th gen) · Core 6th gen · max 35 W

Socketed and replaceable, but only 35 W 6th Gen Skylake T-series (e.g. i5-6500T, i7-6700T) on the Intel Q170 chipset - 65 W desktop SKUs are not supported by the Micro cooling solution. 7th Gen Kaby Lake fits physically but is not officially BIOS-supported (that's the 7050), so treat 6th Gen only as the safe assumption.

No compatible offers right now.