single M.2 SSD with NVMe protocol needs min. 4 lanes for PCIe Gen2 (2GB/s max. bandwidth) for maximize of their performance. But in the QNAP expansion card we can find:
- 2x slots for the M.2 SSD NVMe
- 1x 10Gbps Ethernet NIC
- when someone purchase this QNAP expansion card with PCIe Gen 2 x4 lanes , there is no space for full performance of two NVMe SSD+10Gbps Eth. It's just a waste of money. Bad idea.
Syno's PCIe Gen 3 with 8x lanes can provide max. bandwidth 8GB/s what is enough power for the 2x2GB/s (NVMe) + 1.5GB/s (10G NIC).