PHS-memory 16GB DDR4 ECC SO-DIMM 2666MHz PC4-21300E RAM per QNAP TS-435XeU-4G (SP556142)

When a QNAP TS-435XeU-4G NAS runs out of memory, file transfers stall, virtual machines crash, and the entire storage infrastructure becomes unreliable. This 16GB DDR4 ECC SO-DIMM module solves that by quadrupling the original 4GB capacity and adding error-correcting code to protect data integrity in always-on environments.

Who is it for

IT administrators and small businesses running the QNAP TS-435XeU-4G who need more headroom for virtualization, caching, or simultaneous user access. It is also suitable for other NAS or embedded server systems that accept 260-pin ECC SO-DIMM DDR4 modules at 2666MHz.

Main features

• 16GB capacity – four times the standard 4GB, enabling heavier workloads.
• DDR4 ECC technology – detects and corrects single-bit memory errors automatically.
• 2666MHz speed (PC4-21300E) – balances performance and power efficiency at 1.2V.
• 260-pin SO-DIMM form factor – fits compact NAS and server boards.
• Unbuffered design – low latency for responsive applications.
• Plug-and-play compatibility – no BIOS configuration required for the QNAP TS-435XeU-4G.

Specifications

• Capacity: 16 GB
• Memory type: DDR4
• Module type: SO-DIMM
• Error correction: ECC
• Speed: 2666 MHz
• PC standard: PC4-21300E
• Voltage: 1.2 V
• Pin count: 260-pin
• Buffering: Unbuffered
• Application: NAS / Server
• Compatible device: QNAP TS-435XeU-4G
• Module configuration: Single module
• Data integrity check: Yes
• Manufacturer part number: SP556142

Tips

Before installation, power down the NAS completely and disconnect all cables. Ground yourself to prevent electrostatic discharge. Insert the module at a 30-degree angle into the SO-DIMM slot, then press down until the clips lock. After booting, verify the total memory in QTS under Control Panel > System Status > Hardware Information.