A Look Inside

Breaking apart the DS620slim was easy since I only had to remove several screws and the cooling fan before sliding the side and top plastic cover back.


If you wish to upgrade the RAM, there is an empty slot. You need to remove the base of the NAS to access it.


The server uses DDR3L memory and comes with 2 GB pre-installed, which is enough for its Linux-based OS.


A relatively large mainboard heatsink covers the CPU. There is no need for active cooling due to the low TDP (10 W) of the Intel Celeron J3355 processor.


An integrated T650942A0 power-management chip (PMIC) supports the Intel SoC.


This is a Marvell 88SE9235-NAA2 SATA controller capable of handling up to four SATA ports.


The power button and LED indicators of the front panel are connected to the mainboard through a ribbon cable.


The flash memory shown above only contains the part of the DSM operating system used to boot up the system. The rest of the OS is installed on the drives.


The BIOS battery.


Two REALTEK 8111HS Ethernet controllers handle two Gigabit Ethernet ports.


The EEPROM of the NAS, a Winbond 25Q128FWS IC.


I also found a PIC 16F18345 MCU on the mainboard.


The SATA expansion card can hold up to six drives.


The NAS uses a Kingwei SMD Buzzer.


As per usual for a Synology NAS, cooling duties are handled by a Y.S Tech fan. The model number is FD128020HL, and it measures 80 mm across. The fan can easily be removed for cleaning or replacing purposes.