Dell OptiPlex 7040 Mini Tower upgrades

Released 2015 · end of sale

Mini Tower variant only: the micro chassis has 2 DIMM slots/16 GB max and 35 W CPUs. CPU is socketed (not soldered) and all RAM is removable - no soldered memory. 240 W PSU with no PCIe auxiliary power connectors: discrete GPUs must be slot-powered (<=75 W) unless the PSU is replaced.

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

4x DDR4 UDIMM (non-ECC), up to 64 GB: 4 × DDR4 DIMM · up to 64 GB total · 2133 MT/s
1x M.2 2280: NVMe PCIe 3.0 x4 or SATA: SSD M.2 2280 (NVMe / SATA)
1x 3.5" + 2x 2.5" SATA 6 Gb/s internal bays: 3 × HDD / SSD 3.5" / 2.5" (SATA) · up to 2 TB
1x LGA 1151 socket (6th Gen Intel Skylake): LGA1151 (6th/7th gen) · Ryzen 3000 · max 65 W

Slot map

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

4x DDR4 UDIMM (non-ECC), up to 64 GB 4 × DDR4 DIMM · up to 64 GB total · 2133 MT/s

288-pin desktop UDIMMs (not SO-DIMM), dual-channel. Dell validates only 8 GB modules/32 GB total; Kingston, MemoryCow and user reports confirm 4x16 GB = 64 GB works (outside Dell spec). DDR4-2400/2666/3200 will downclock to 2133 MT/s - no XMP. Non-ECC UDIMM only; ECC/RDIMM will not work.

No compatible offers right now.

1x M.2 2280: NVMe PCIe 3.0 x4 or SATA SSD M.2 2280 (NVMe / SATA)

Socket 3, 22x80 mm only - 2230/2242/22110 need an adapter. Full PCIe 3.0 x4 speed confirmed (~3,000 MB/s with a Samsung 970 EVO Plus). A heatsink/thermal pad is recommended; no heatsink is supplied. No minimum PCIe generation is required by Dell.

No compatible offers right now.

1x 3.5" + 2x 2.5" SATA 6 Gb/s internal bays 3 × HDD / SSD 3.5" / 2.5" (SATA) · up to 2 TB

4x SATA 6 Gb/s ports; RAID 0/1 supported on some configs. 2 TB is Dell's documented factory maximum per drive - larger third-party drives may work but are untested. The 3.5" bay can convert to the 5.25" slim ODD bay; caddies/screws may be missing in used units.

No compatible offers right now.

1x LGA 1151 socket (6th Gen Intel Skylake) LGA1151 (6th/7th gen) · Ryzen 3000 · max 65 W

cpu_families entry 'ryzen_3000' is a placeholder error in source parsing; only 6th Gen Intel Skylake CPUs (Celeron/Pentium through Core i7-6700) are supported on Q170 with Dell's BIOS. 7th Gen Kaby Lake chips fit LGA 1151 physically but are NOT supported - do not buy 7xxx CPUs. MT/SFF limit is 65 W TDP.

No compatible offers right now.