DeepSeek V4.1 Flash hands-on tests and comparisons

Running DeepSeek V4.1 Flash 1017 at IQ2_XXS on a single RTX 4090 48GB with the Strata engine, disabling SSD cache and keeping experts in RAM raised generation from 5.35 to 42.64 tok/s and cut first-token latency from 33s to 0.66s.

In a reply thread, a user says DeepSeek 1017 is really good but Opus 5.5 one-shots essentially every task, and they'll drop subscriptions once local models match it.

The author recommends DSH for official-harness users and PI or Grok build for third-party setups when running DeepSeek V4.1 Flash 1017.

Using Claude Code with DeepSeek Flash 1017 at xhigh thinking plus a remotion-best-practices skill, the author made an intro animation and a 52-second media kit video for under 3 yuan total, with cache hit rate above 98%.

On the same write-test-fix task, OpenCode with Ollama Cloud took ~6s, dsh with Ollama Cloud ~8s, OpenCode with OpenCode Go ~14s, and Claude Code with Ollama 27-48s, concluding the harness is the bottleneck.

The author says this GUI-free terminal agent turns one prompt into webpages, editable PPTX, app prototypes and infographics, and is tuned for DeepSeek-V4.1-flash-1017, though no test numbers are given.

A beginner's first guide covering API key setup, base_url and model names, a first request, plus V4.1-Flash-1017's 1M context and per-million-token pricing.

An analysis of DeepSeek's disclosed inference economics: 155T tokens per day per cluster, roughly $38 of billable revenue per GPU-hour at off-peak API prices, though DeepInfer leaves key serving components closed.

The release swaps in new weights across web, app and API; DeepSeek claims shorter outputs, faster tasks and higher coding/agent scores in its own tests, with Harness v0.2.1-rc.1, open Search/Fetch APIs and HuggingFace weights.

Cites OpenRouter usage showing V4.1 Flash at 36.94 trillion tokens over 7 days and about 124 trillion over 30 days, arguing low-cost handling of massive real demand is reshaping the competitive landscape.

LMSYS benchmarked SGLang against DeepSeek's own DeepInfer engine on V4.1 Flash: up to ~1.04x prefill and ~7.4% faster decode steps on 64x GB300, with built-in KV cache and P-D disaggregation.

A user testing OpenGateway's deepseek-v4.1-flash-ultrafast found speeds underwhelming, while the official DeepSeek API reached about 260 tok/s and felt faster.