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Coding · 2026-09-27

Qwen 3.8 27B on a single RTX 4090, measured (llama.cpp)

A documented, measured local coding setup: Qwen 3.8 27B on one RTX 4090 with llama.cpp and OpenCode, holding a 128k context and reporting around 92 tokens/s generation with speculative decoding.

An open-source project (awesome-local-ai) ships one-command installers that pair a model with hardware and a stack, and records every performance and memory figure on real hardware rather than estimating it.

Measured reference combination

  • Hardware: a single RTX 4090 (24GB)
  • Stack: Qwen 3.8 27B served by llama.cpp to OpenCode, at a 128k context
  • Speed: ~92 tok/s generation with speculative decoding on, ~44 with it off; the installer asserts the draft acceptance appears in the log before calling the install good
  • Vision: a native vision tower is available but off by default; loading it costs 32k of context on a 24GB card (128k down to 96k), a VRAM trade rather than a missing capability

The same project runs a build benchmark (Vidi) that drives a coding agent through a real 17-story specification and scores the result with a held-out test suite the agent cannot read. Setup, hardware, stack and the benchmark methodology are documented in the repository.

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SETUP HISTORY

Snapshots over time

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CURRENT2026-09-27Qwen 3.8 27B on a single RTX 4090, measured (llama.cpp)

A documented, measured local coding setup: Qwen 3.8 27B on one RTX 4090 with llama.cpp and OpenCode, holding a 128k context and reporting around 92 tokens/s generation with speculative decoding.

Coding1 machineQwen 3.8 27Bllama.cpp
ChangedDescription
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DescriptionPreviousAn open-source project (awesome-local-ai) ships one-command installers that pair a model with hardware and a stack, and records every performance and memory figure on real hardware rather than estimating it. This is its measured reference combination for a single RTX 4090 (24GB): Qwen 3.8 27B served by llama.cpp to OpenCode, at a 128k context. The author reports roughly 92 tokens/s generation with speculative decoding on, against about 44 with it off, and the installer asserts the draft acceptance appears in the log before calling the install good. A native vision tower is available but off by default: loading it costs 32k of context on a 24GB card (128k down to 96k), a VRAM trade rather than a missing capability. The same project runs a build benchmark (Vidi) that drives a coding agent through a real 17-story specification and scores the result with a held-out test suite the agent cannot read. Setup, hardware, stack and the benchmark methodology are documented in the repository.This snapshotAn open-source project (`awesome-local-ai`) ships one-command installers that pair a model with hardware and a stack, and records every performance and memory figure on real hardware rather than estimating it. ## Measured reference combination - **Hardware**: a single RTX 4090 (24GB) - **Stack**: Qwen 3.8 27B served by llama.cpp to OpenCode, at a 128k context - **Speed**: ~92 tok/s generation with speculative decoding on, ~44 with it off; the installer asserts the draft acceptance appears in the log before calling the install good - **Vision**: a native vision tower is available but off by default; loading it costs 32k of context on a 24GB card (128k down to 96k), a VRAM trade rather than a missing capability The same project runs a build benchmark (Vidi) that drives a coding agent through a real 17-story specification and scores the result with a held-out test suite the agent cannot read. Setup, hardware, stack and the benchmark methodology are documented in the repository.

This is the currently published snapshot.

REVISION 12026-09-27Qwen 3.8 27B on a single RTX 4090, measured (llama.cpp)

A documented, measured local coding setup: Qwen 3.8 27B on one RTX 4090 with llama.cpp and OpenCode, holding a 128k context and reporting around 92 tokens/s generation with speculative decoding.

Coding1 machineQwen 3.8 27Bllama.cpp

Archived published snapshot — kept for context and comparison.

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