HP Inc. HP EliteDesk 800 G4 Tower PC upgrades

Released 2018 · support ended

HP EliteDesk 800 G4 Tower (TWR/MT, Q370): CPU is socketed (LGA1151v2 slot above) and all four DIMM sockets are user-accessible with no soldered memory. Do not confuse with the SFF, Desktop Mini (SO-DIMMs) or 880 G4 variants. 32-bit OS cannot use >~3 GB; 64-bit Windows required for >4 GB.

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

4× DDR4 DIMM (non-ECC, 64 GB max): 4 × DDR4 DIMM · up to 64 GB total · 2666 MT/s
2× M.2 2280/2230 NVMe (PCIe 3.0 x4): 2 × SSD M.2 2230 / M.2 2280 (NVMe)
3× SATA 6 Gb/s bays (2× 3.5", 1× 2.5"): 3 × HDD / SSD 2.5" / 3.5" (SATA)
LGA1151v2 CPU socket (8th Gen Intel): LGA1151 (8th/9th gen) · Core 8th gen · max 95 W

Slot map

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

4× DDR4 DIMM (non-ECC, 64 GB max) 4 × DDR4 DIMM · up to 64 GB total · 2666 MT/s

Unbuffered non-ECC DDR4 only (HP warns unsupported modules may not work); avoid x4-device and RDIMM/ECC sticks. 2666 MT/s only with 8th-gen i5/i7; i3/Pentium/Celeron cap at 2400. 32 GB UDIMMs not validated — 64 GB = 4×16 GB. Service manual says DDR4-2400 CL17, spec sheets say 2666; both work (faster sticks downclock). All four slots user-accessible, nothing soldered.

No compatible offers right now.

2× M.2 2280/2230 NVMe (PCIe 3.0 x4) 2 × SSD M.2 2230 / M.2 2280 (NVMe)

Two storage M.2 slots (plus a separate M.2 2230 PCIe x1 WLAN slot that cannot take drives). PCIe 3.0 x4 wiring; HP does not document M.2 SATA support in these slots on the TWR, so assume NVMe only. No HP-documented capacity cap (largest factory option 1 TB); 2230 drives need a spacer/screw position for that length.

No compatible offers right now.

3× SATA 6 Gb/s bays (2× 3.5", 1× 2.5") 3 × HDD / SSD 2.5" / 3.5" (SATA)

Two 3.5" bays plus one dedicated 2.5" bay, SATA 6 Gb/s. 2.5" drives fit the 3.5" bays only with an adapter/caddy. No documented capacity limit (largest factory HDD 2 TB). One free 5.25" half-height bay for an optical/HDD cage or optional SD card reader.

No compatible offers right now.

LGA1151v2 CPU socket (8th Gen Intel) LGA1151 (8th/9th gen) · Core 8th gen · max 95 W

Socketed and replaceable (Q370 chipset). HP lists 8th-gen Coffee Lake-S only — Core i3/i5/i7, Pentium Gold, Celeron; 9th-gen parts (e.g. i9-9900) are not officially supported despite the same physical socket. Highest listed TDP is 95 W (i7-8700K/i5-8600K, Workstation Edition); stock ~250 W PSU limits GPU upgrades, so a bigger HP 880 G4 supply may be needed.

No compatible offers right now.