Last year I actually tried a less expensive non-Synology branded "equivalent" memory card for my DS620slim. It didn't work properly and that old card was removed before the day ended.
Recently I thought to give the 4GB upgrade another go. This one is genuine Synology all the way, including the sealed outer Synology packaging. Your mileage may vary, but I am sold on this genuine Synology-branded memory for my DS620slim.
(Update June 2023) The DRAM and NAS have been running completely trouble-free for two months. But the reason for appending this review is to relate my experience with the space/performance trade-off.
Many mornings I copy a very large non-compressible data file from a PC to a share on the NAS. Prior to any memory upgrade, this transfer typically topped out at about 20MB/sec. Following the memory upgrade (so a 2GB to 6GB transition), the transfer started topping out at about 30MB/sec.
I was still running the default "Compression on" setting for the Synology data buffers. I suspected that "Compression on" was just burning needless CPU cycles and possibly slowing down the transfers. At the next opportunity when I needed to restart the Synology anyway (for an unrelated reason), I changed the setting to "Compression off".
Guess what - the file transfers now top out at about 38MB/sec. This observation sure exemplifies the benefit of a lot of buffer memory in the Synology DS620slim NAS.
| Memory Speed | 1600 MHz |
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