DeepSeek V4.1 Flash on 4 DGX Sparks: second RoCE cable lifts long-prompt reads 15%

Tech2Wild @Tech2WildOriginally posted 2026.10.18

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🧠 Why a 2nd cable = more speed: DeepSeek V4.1 Flash is too big for one DGX Spark, so it's split across 4. Every step, the Sparks swap their work over RoCE. 1 cable = 1 lane. 2 cables = double the lanes 🛣️ Long prompts move the most data, so reading them jumped +15% 📖

This post quotes another post: “DeepSeek V4.1 Flash on dual-cable DGX Spark: 93.6 tok/s single user”