Dell OptiPlex 3040 Small Form Factor upgrades

Released 2015 · on sale

Dell OptiPlex 3040 SFF: H110-based Skylake platform. Upgrade essentials: DDR3L-1600 UDIMMs only (not DDR4, not SO-DIMM), 16 GB max, no M.2/NVMe slot (SATA boot only). 180 W PSU plus half-height-only PCIe slots (1x Gen3 x16 + 1x x1) limit GPU choices to low-profile, low-power cards. Storage documentation is inconsistent on the number of 5.25" bays; assume one 3.5" + one slim optical bay internally. These specs apply to the SFF - the MT has a 240 W PSU and two 3.5" bays, the Micro uses SO-DIMMs and an M.2 2230 slot.

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

2x DDR3L-1600 UDIMM (desktop), 16 GB max: 2 × DDR3 DIMM · up to 16 GB total · 1600 MT/s
SATA 6 Gbps: 3.5" + 2.5" internal bays: 2 × SSD / HDD 3.5" / 2.5" (SATA)
1x LGA1151 socket (Skylake only), 65 W: LGA1151 (6th/7th gen) · Core 6th gen · max 65 W

Slot map

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

2x DDR3L-1600 UDIMM (desktop), 16 GB max 2 × DDR3 DIMM · up to 16 GB total · 1600 MT/s

DDR3L (1.35 V) UDIMMs only - full-length desktop DIMMs, not SO-DIMMs; standard 1.5 V DDR3 and DDR4 won't work. 16 GB (2x8 GB) is the BIOS/platform ceiling. Manual states min 4 GB per slot; buy 2x4 GB or 2x8 GB PC3L-12800 non-ECC.

No compatible offers right now.

SATA 6 Gbps: 3.5" + 2.5" internal bays 2 × SSD / HDD 3.5" / 2.5" (SATA)

One 3.5" bay plus one 2.5" position (bracket/caddy usually needed). No M.2/NVMe - boot drive must be SATA. 2.5" SSD is the best upgrade; no documented capacity limit, but the 180 W PSU and single 3.5" bay are the practical limits. Sources disagree on external 5.25" bay count (one or two) - verify the chassis if an ODD/card-reader build matters.

No compatible offers right now.

1x LGA1151 socket (Skylake only), 65 W LGA1151 (6th/7th gen) · Core 6th gen · max 65 W

Socketed and replaceable, but Dell's BIOS supports 6th Gen Skylake only (Core i3/i5/i7, Pentium, Celeron) - 7th Gen and 8th/9th Gen are not supported. 65 W limit rules out K-series parts (e.g. i7-6700K) officially; top supported parts are i5-6500/6600 and i7-6700. Match the existing cooler/PSU headroom before swapping CPUs.

No compatible offers right now.