| Brand | QNAP |
| EAN | 4713213516676 |
| ASIN | B083QRD6L3 |
| MPN | TS-251D-4G |
| SKU | TS-251D-4G |
| AC input frequency | 50 - 60 Hz |
| AC input voltage | 100 - 240 V |
| Access Control List ACL | Yes |
| Backup features | Cloud, USB drive |
| Browser supported | Apple Safari 7+, Google Chrome, Microsoft Internet Explorer 10+, Mozilla Firefox |
| Cable lock slot type | Kensington |
| Cables included | AC, LAN (RJ-45) |
| Chassis type | Tower |
| Colour | White |
| Cooling type | Active |
| Device class | Home & Home Office |
| Embedded options available | No |
| Ethernet LAN data rates | 1000 Mbit/s |
| Ethernet LAN ports | 1 |
| Execution units | 12 |
| Fan diameter | 7 cm |
| Flash memory | 4000 MB |
| Harmonized System HS code | 84714100 |
| HDMI version | 2.0 |
| Intel Identity Protection Technology version | 1.00 |
| Intel Smart Response Technology version | 0.00 |
| Internal memory | 4 GB |
| LED indicators | HDD, LAN, Power, Status, USB |
| Maximum displays supported | 3 |
| Maximum internal memory supported by processor | 8 GB |
| Maximum PCI Express lanes | 6 |
| Memory form factor | SO-DIMM |
| Memory slots | 2 |
| Memory types supported by processor | DDR4-SDRAM, LPDDR4-SDRAM |
| Noise Level | 16.7 dB |
| Number of screws | 14 |
| On-board graphics adapter base frequency | 250 MHz |
| On-board graphics adapter burst frequency | 700 MHz |
| On-board graphics adapter DirectX version | 12.0 |
| On-board graphics adapter ID | 0x3185 |
| Onboard graphics adapter model | Intel® UHD Graphics 600 |
| Operating relative humidity | 5 - 95% |
| Operating system installed | QNAP QTS |
| Operating temperature | 0 - 40 °C |
| PCI Express configurations | 1x2, 1x2+2x1, 1x4, 2x1, 4x1 |
| Power consumption | 15.25 W |
| Power consumption sleep | 8.08 W |
| Power supply location | External |
| Power supply unit PSU capacity | 65 W |
| Processor ARK ID | 128992 |
| Processor boost frequency | 2.7 GHz |
| Processor codename | Gemini Lake |
| Processor family | Intel® Celeron® |
| Processor operating modes | 64-bit |
| Processor package size | 25 x 24 mm |
| Processor socket | BGA 1090 |
| RAID levels | 0, 1, JBOD |
| Security algorithms | 256-bit AES, FIPS 140-2, SNMPv3, SSH, SSL/TLS |
| Share folder | CIFS/SMB, FTP, WebDAV |
| Storage drive sizes supported | 3.5" |
| Storage temperature | -20 - 70 °C |
| Supported file systems | FAT32, HFS+, NTFS, ext3, ext4 |
| Supported storage drive interfaces | Serial ATA II, Serial ATA III |
| Supported storage drive types | HDD & SSD |
| Thermal design power | 10 W |
| Tjunction | 105 °C |
| Windows operating systems supported | Windows 10, Windows 7, Windows 8 |