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Learn · NVIDIA Hardware & DGX · DGX Spark Clustering & MikroTik Switches

MikroTik 100G & 400G Switches (CRS504, CRS804, CRS812)

In plain English

If you connect two or four DGX Sparks together, they need an ultra-fast private highway to share their thoughts. MikroTik makes quiet, affordable desktop switches like the CRS504 (100G) and CRS804 (400G) that give your AI cluster datacenter speed without datacenter noise! 🔌

What is actually going on

Clustering DGX Spark GB10 units requires sub-microsecond RDMA switching. The MikroTik CRS504-4XQ-IN offers 4x 100G QSFP28 ports with ~25W power draw for ~$799, making it the ideal quiet desktop backbone for 2-4 Spark clusters. For ultra-dense bandwidth, the CRS804-4C-IN provides 4x 400G QSFP-DD ports (3.2 Tbps aggregate), and the CRS812-8C-4XQ-IN provides 8x 400G + 4x 100G for multi-node labs running RoCEv2 priority flow control (PFC).

Why it matters

Without high-speed 100G/400G interconnects, multi-node tensor parallelism collapses under communication latency. MikroTik switches make desk-side 100G/400G networking affordable for local AI builders.

Another way to think about it

A dedicated high-speed fiber tunnel between twin supercomputers so they can finish each other's sentences at 100 Gbps. 🏎️💨

Check yourself

  1. Which compact 100G switch is popular for 2–4 DGX Spark clusters?

    • MikroTik CRS504-4XQ-IN
    • Netgear 1G 5-port
    • Cisco 6500 chassis
    • USB-C Hub
    Show answer

    MikroTik CRS504-4XQ-IN — The CRS504 provides 4x 100G QSFP28 ports in a quiet, low-power (~25W) desktop form factor for ~$799.

  2. What port speed does the MikroTik CRS804-4C-IN deliver?

    • 10 Gbps
    • 40 Gbps
    • 100 Gbps
    • 400 Gbps
    Show answer

    400 Gbps — The CRS804 provides 4x 400G QSFP-DD ports for ultra-high-density inter-node bandwidth.

  3. RoCEv2 enables direct GPU-to-GPU memory transfer over Ethernet without CPU overhead.

    • True
    • False
    Show answer

    True — RDMA over Converged Ethernet (RoCEv2) bypasses the CPU and host OS stack for sub-2µs latency.

Terms from this lesson

MikroTik CRS504-4XQ-INDGX Spark