Run FULL DeepSeek v4.1 Flash on a 12GB GPU
A developer ran DeepSeek v4.1 Flash on a 12GB gaming GPU. We compare three routes, RAM and SSD needs, real speeds, and whether the 2-bit copy is still DeepSeek.
A developer at a small UK company recently ran the full DeepSeek v4.1 Flash on a five-year-old gaming PC. The model's original weights total 510 GB. The test machine had an NVIDIA RTX 3060 with 12 GB of video memory and 64 GB of system RAM. The model has 763 billion parameters. The developer reported speeds of up to 7.4 tokens per second. The project had about 30 stars on GitHub at the time.
The most widely used engine for this setup, Strata, has over 37,000 GitHub stars. Many video demonstrations show DeepSeek running on 12 GB cards. Most of these demonstrations do not mention that Strata runs a compressed copy of the model, not the original release. On any card with 16 GB of memory or less, Strata also disables one of the six experts that the model normally activates for each token by default.
This article covers three ways to run DeepSeek on a 12 GB card. It describes the RAM and storage each route requires, the speeds reported by the developers and by independent users, and whether the compressed versions remain DeepSeek in practice.
Background: Why the Model Fits on a Gaming Card
DeepSeek v4.1 Flash 1017 was released on October 17. It is licensed under MIT. The model is one of the strongest open-weight models available for download. Its download size is 510 GB.
Two architectural features make local operation possible:
- Mixture of experts (MoE): The model has 40 layers with 384 experts in each layer. Only six experts activate for any given token.
- N-gram lookup tables: The model includes 196 billion parameters in N-gram lookup tables. Each token reads only a few rows from these tables.
Because most of the model remains inactive for any given token, the system can distribute the model across three storage tiers:
| Storage tier | Contents |
|---|---|
| GPU (VRAM) | The small set of components every token needs |
| System RAM | Experts that activate frequently |
| SSD | All remaining weights |
In this setup, the SSD becomes a working part of inference. One tester's drive read 2.2 TB during 19 minutes of use. That amount is about nine times the size of the model file. The same drive wrote only about 1 GB. The workload is read-intensive, not write-intensive, so the tester's drive wear risk is low.
Route 1: Strata
Strata is a free, open-source engine on GitHub. It runs a compressed version of DeepSeek created by Ista, a research lab in Austria.
Requirements
| Component | Requirement |
|---|---|
| GPU | NVIDIA RTX 30, 40, or 50 series with 12 GB on Windows or Linux, or AMD R9 700 on Linux |
| System RAM | At least 46 GB; 64 GB recommended |
| Storage | About 257 GB free on a fast SSD |
Strata's documentation describes configurations below about 40 GB of RAM as untested and slow.
Setup
Setup requires one command. The user specifies the model family and file. Strata downloads all required components and starts a local server.
Speed: Developer-Reported Figures
Strata's documentation reports the following results:
- RTX 3060 with 46 GB of RAM: 8 to 10 tokens per second
- RTX 5070 with 64 GB of RAM: about 4.7 tokens per second
The older card is faster. When most of the model resides outside the GPU, the GPU spends most of its time waiting for data from other components.
Speed: Independent Results
| Tester | Hardware | Prompt processing | Output generation |
|---|---|---|---|
| AI Receipts | RTX 5070, 32 GB RAM | 90 to 123 tokens/s | 1.84 tokens/s |
| Unnamed tester ("No code about") | RTX 4070 Super, 32 GB RAM, 1.75-bit file | Not reported | About 2.8 tokens/s |
| Inference Guru | RTX 5070, 64 GB RAM | Not reported | Up to 9.2 tokens/s |
RAM capacity determines performance more than GPU capacity. With 64 GB, the model runs slowly but usably. With 32 GB, output arrives one word at a time.
Quality of the Compressed Files
Ista reports that its two-bit version retains 100% of the original model's average score across three difficult reasoning benchmarks. Two points qualify this result:
- The original model scores 100 on one of the three benchmarks. That column cannot show a loss.
- The file labeled "two-bit" is not uniformly two-bit. Half of its expert layers use a 1.75-bit format. The two-bit figure is an average.
Strata's team measured divergence from the original model directly. They compared word predictions of the compressed copies against the original over about 5,000 positions. Perplexity measures how surprised a model is by real text. Results:
| File | Perplexity drift | Plain English prose drift |
|---|---|---|
| Two-bit | 15.5% | Not reported |
| 1.75-bit | 21% | 53% |
Code and agent tasks showed single-digit drift, which is considerably smaller than the drift on prose.
On a 12 GB card, Strata's default fast mode also runs five experts instead of six.
Side-by-Side Test
AI Receipts is the only independent tester identified who compared the local copy with DeepSeek's cloud version on the same task. Both received the prompt: build a cart racing game in one web page.
- Local copy: Ran on an RTX 5070 with a 20,000-token context window. It produced 13,000 tokens in 2 hours and 6 minutes. The page ran without errors.
- Cloud version: Used DeepSeek's API.
- Grading: Two AI reviewers graded both games blind, out of 12 points. The cloud version scored 10. The local copy scored 2.
Each model ran once, with thinking disabled and fast mode enabled. The result does not prove that the local copy is broken. It does show a large difference on this task. At DeepSeek's off-peak price, 13,000 output tokens cost less than one cent.
Route 2: Prometheus
Prometheus is a Windows engine developed by Ryan Flavel, a developer who built it with AI coding assistants. The name is spelled with a V, the historical Roman spelling. It is also the name of a UK company, Magnus, which is spelled with a V.
Unlike Strata, Prometheus runs the original DeepSeek weights.
Why Not Run the Original Weights Directly?
The author measured plain, exact decoding of the full model on the test PC. The result was 2.14 tokens per second. That speed is too slow for practical use.
Compress, Then Correct
Prometheus uses a two-stage process:
- Initial computation: Each token is first computed using the two-bit copy of the experts, as in Strata.
- Confidence check: At every token, the engine checks the model's confidence. If the top two candidate tokens are closer in probability than a fixed margin, the engine discards the token and recomputes it with the original weights. The original weights are reconstructed from the two-bit copy plus a set of correction layers.
A small draft head also predicts several tokens ahead. The engine verifies these predictions in parallel.
The developer describes this as a student who answers most questions from summary notes and consults the full textbook only when two answers appear equally correct.
Requirements
| Component | Requirement |
|---|---|
| Operating system | Windows only |
| GPU | RTX 30 or 40 series only |
| System RAM | 64 GB |
| CPU | 16-core recommended |
| Storage | About 1.1 TB free SSD space |
The storage requirement exceeds twice the model size. Prometheus stores the original weights, the two-bit copy, and the correction layers side by side. A 2 TB SSD currently costs about $250.
Setup
- Step 1: Download 510 GB of model files.
- Step 2: Run a build that takes about 4 hours while it prepares the copies.
Speed
The developer reports a best-case speed of 7.4 tokens per second. The developer states that this figure does not represent a typical session.
| Test | Hardware | Result |
|---|---|---|
| Cold start | Ryzen CPU, 64 GB DDR4, RTX 3060 | 5.8 tokens/s (code) |
| Warm | Same | 7.4 tokens/s (code) |
| Reasoning and agent prompts | Same | About 4.5 to 5 tokens/s |
The developer reports that these results are about 2.7 times faster than running the plain original weights. They match the Strata 64 GB results.
With a prompt of about 1,100 tokens, the first word took about 2 minutes to appear. Follow-up messages began in about 2 seconds. The initial delay affects workloads that load large amounts of context at the start of each task, such as coding agents that read a large portion of a code repository for every task.
Output Quality
The developer compared Prometheus with the same engine running only the original weights:
- Short tests (960 words): Output matched 99.17% of the time.
- Longer agent prompt: Output matched 95.9% of the time, counting every difference. This result falls below the developer's target of 97%.
The 99% figure measures agreement with the engine's own exact mode. It does not measure agreement with DeepSeek's reference code. The developer states that they have not yet run that comparison.
Limitations of the Evidence
The developer states that all results come from one machine, one model, and one family of prompts. As of the time of writing, no one has reported a clean installation on a second PC. The release archive has been downloaded 39 times. The repository's issues section contains a benchmark template for independent testing.
Route 3: llama.cpp
llama.cpp is the general-purpose route. Support for this model was merged into the main llama.cpp branch on October 25. Unsloth publishes compressed versions of the model with a setup guide.
For 12 GB cards, this route is not yet practical:
- Unsloth's guide states that its smallest one-bit version requires about 128 GB of combined RAM and VRAM.
- The guide describes 64 GB as "possible but slower" and does not provide a speed figure.
- No published main-branch result on a 12 GB card was identified.
The closest published result comes from a llama.cpp reviewer using an AMD R9 700 with an RTX 5060 and 128 GB of RAM. That configuration produced about 6.5 tokens per second for output and 31 tokens per second for reading. The reviewer described the reading speed as "somewhat disappointing."
Why llama.cpp Is Slower Here
llama.cpp maps the model file into memory and lets the operating system load sections from the SSD as needed. Strata tested this approach on an RTX 5070 system with 64 GB of RAM. It achieved 1.8 to 2.2 tokens per second. Strata's direct read method, which reads from the drive using its own approach, achieved 4.3 to 4.9 tokens per second.
When half of the model resides on the SSD, the method used to read the drive affects performance more than the GPU does.
Hardware Checklist
Ranked by impact:
- System RAM: Determines which routes are viable.
- 32 GB: DeepSeek on a 12 GB card is a long-running batch task, not an interactive chat.
- 64 GB: Both Strata and Prometheus are viable.
- GPU: Upgrading is unnecessary. The RTX 3060 is the reference card for both Strata and Prometheus.
- SSD: Use a fast NVMe drive. SATA SSDs and hard drives are not suitable.
- Strata: 257 GB free.
- Prometheus: 1.1 TB free.
- Strata file selection:
- For code and agent tasks, the two-bit file is suitable.
- For long-form writing, avoid the 1.75-bit file. It shows 53% drift on prose.
- For output that requires maximum accuracy, enable full quality mode, which runs all six experts.
- Background GPU load: Close other applications that use the GPU. Each gigabyte that other applications use must be supplied by slower storage.
- Thinking mode: Strata enables DeepSeek's thinking mode by default. For short tasks, disable it. At 2 to 7 tokens per second, a model that generates 1,000 reasoning tokens before answering takes several minutes per response.
Recommendations by Hardware
| Configuration | Recommendation |
|---|---|
| 12 GB GPU, 32 GB RAM | Do not run DeepSeek locally. Use a model sized for the machine, and use DeepSeek's API for large tasks. |
| 64 GB RAM, RTX GPU | Use Strata with the two-bit file for code and agent work. Enable full quality mode for high-stakes output. Evaluate results on your own tasks. |
| RTX 30 or 40 series, 64 GB RAM, Windows, 2 TB spare SSD | Try Prometheus. It is the closest available approximation of the original model on a gaming PC. Expect a long initial setup. |
| Mac with 64 GB or more | Strata released a text-only Mac build the previous week. Few performance figures are available. |
| Mac with less than 64 GB | Strata's Mac build requires at least 64 GB of unified memory. |
| 24 GB GPU, 90 GB RAM | One developer's fork of Strata reports about 26 tokens per second on an RTX 4090 with DDR4 RAM. This is a single result on one system. |
For speed and accuracy on the full model, DeepSeek's API runs the original model faster than any local route in this article. The cost of the cart-racing test was under one cent.
Summary
DeepSeek v4.1 Flash can now run on a 12 GB GPU, provided the system has sufficient RAM and fast storage. Whether the result is still DeepSeek depends on the route:
- Strata runs compressed files. Its reported quality retention varies by task type. On the single independent side-by-side test, the local copy scored 2 out of 12 against the cloud version's 10.
- Prometheus runs the original weights through a verification process. Its reported output agreement is 99.17% on short tests and 95.9% on a longer agent prompt. Its results have not been reproduced on a second system.
- llama.cpp does not yet provide published results on 12 GB cards.
Introduction and the Claim
The presenter introduces the claim of running the full DeepSeek v4.1 Flash on a 12 GB card and previews the three routes and the question of whether the compressed copy is still DeepSeek.
- A lone developer at a tiny UK company ran the full DeepSeek v4.1 Flash on a 5-year-old gaming PC.
- Original weights are 510 GB, run on an RTX 3060 with 12 GB VRAM and 64 GB RAM.
- Model is 763 billion parameters; reported speed up to 7.4 tokens per second.
- The Strata engine has over 37,000 GitHub stars; the Prometheus project has 30.
- Strata runs a 2-bit copy and, on cards with 16 GB or less, switches off one of the six experts per word by default.
Why the Model Fits on a Gaming Card
DeepSeek v4.1 Flash is an MIT-licensed mixture-of-experts model. Only a few pieces are needed for each word, so the GPU, RAM, and SSD each hold different parts of the model.
- DeepSeek v4.1 Flash 1017 was released October 17th and is MIT licensed.
- The model has 40 layers with 384 experts each; only six activate per word.
- It includes 196 billion parameters of N-gram lookup tables, where each word reads only a few rows.
- The GPU holds the shared pieces every word needs, RAM holds frequently used experts, and the SSD holds everything else.
- One tester's drive read 2.2 TB in 19 minutes (about nine times the model size) and wrote only about 1 GB.
Route One: Strata
Strata is a free engine that runs a compressed DeepSeek copy made by an Austrian research lab. It needs an RTX 30/40/50 card with 12 GB (or AMD R9 700 on Linux), 46 to 64 GB RAM, and about 257 GB of fast SSD space.
- Requirements: RTX 30, 40, or 50 series with 12 GB on Windows or Linux, or AMD R9 700 on Linux.
- Strata's docs say below about 40 GB RAM the setup is untested and slow; 46 GB minimum, 64 GB comfortable.
- About 257 GB of free space on a fast SSD is needed.
- Setup is one line: the user names the model family and file, and Strata downloads everything and starts a server.
- Strata's docs: RTX 3060 with 46 GB RAM writes 8 to 10 tokens per second; RTX 5070 with 64 GB writes about 4.7.
Speed Results and Outside Testing
Outside testers got lower speeds than the developers' figures. Results show RAM size matters more than GPU choice. The 2-bit copy is still arguably DeepSeek, but quality drifts, especially on prose.
- AI Receipts on a 5070 with 32 GB RAM: prompt reading 90 to 123 tokens/s, writing 1.84 tokens/s.
- A 4070 Super with 32 GB RAM on the 1.75-bit file reached about 2.8 tokens/s (reported by No Code About).
- Inference Guru with a 5070 and 64 GB RAM reports up to 9.2 tokens/s.
- The presenter concludes RAM decides speed more than the graphics card: 64 GB is slow but usable, 32 GB is very slow.
- The lab says the 2-bit version keeps 100% of the original's average on three reasoning benchmarks; the presenter notes the original scores 100 on one test, so that column cannot show loss.
Is It Still DeepSeek?
The 2-bit file is not uniformly 2-bit; half its expert layers use 1.75-bit. Strata's own perplexity measurements show drift, and default fast mode runs five experts instead of six on 12 GB cards.
- Half of the expert layers in the 2-bit file use a 1.75-bit format; 2-bit is an average, not a floor.
- Strata compared word predictions to the original over about 5,000 positions.
- Perplexity drift: 2-bit file 15.5%, 1.75-bit file 21%; plain English prose 53%; code and agent work in single digits.
- On a 12 GB card, Strata's default fast mode runs five experts instead of six.
Real-World Test: Cart Racing Game
AI Receipts ran a side-by-side test asking both the cloud and local copies to build a cart racing game in one web page. The cloud version scored 10 out of 12 and the local copy scored 2 in blind AI-reviewer grading.
- Prompt: build a cart racing game in one web page.
- Local copy on a 5070 with a 20,000-token window wrote 13,000 tokens in 2 hours 6 minutes; the page ran without errors.
- Two AI reviewers graded both games blind out of 12: cloud 10, local 2.
- The test was one run each, with thinking off and fast mode on.
- At DeepSeek's off-peak price, 13,000 output tokens cost less than 1 cent.
Route Two: Prometheus
Prometheus, a Windows engine by developer Ryan Flavel, runs the original DeepSeek weights. It drafts with a 2-bit copy and only recomputes uncertain words with the original weights, using a draft head to predict words ahead.
- Prometheus is spelled with a V and is named after the Roman spelling; it comes from a UK company called Magnus.
- Plain exact decoding of the full model on the author's PC runs at 2.14 tokens per second.
- Compress-then-correct: every word is first computed on a 2-bit copy; if the top two choices are closer than a fixed margin, the word is recomputed with original weights rebuilt from the 2-bit copy plus correction layers.
- A small draft head guesses several words ahead and the engine checks them in parallel.
- On a Ryzen with 64 GB DDR4 and an RTX 3060: 5.8 tokens/s cold start, 7.4 warm; reasoning and agent prompts about 4.5 to 5; roughly 2.7 times faster than plain original.
Prometheus Quality, Costs, and Caveats
Prometheus claims 99.17% match with the engine's exact-original-weight mode on 960 words, but it has real limits: Windows-only, RTX 30/40 only, 64 GB RAM, about 1.1 TB SSD, a long build, and slow first-word latency.
- Output matched the same engine's original-weights-only output 99.17% of the time over 960 words.
- Limits: Windows-only; supports only RTX 30 and 40 series; a 16-core CPU is recommended; wants 64 GB RAM.
- Needs about 1.1 TB of free SSD because it stores original weights, the 2-bit copy, and correction layers side by side.
- Setup involves a 510 GB download and a build of about 4 hours.
- A prompt of about 1,100 tokens took about 2 minutes for the first word; follow-up messages start in about 2 seconds.
- On a longer agent prompt, the match was 95.9%, below the author's target of 97%.
- All numbers come from one machine, one model, and one prompt family; the release zip was downloaded 39 times.
Route Three: llama.cpp
llama.cpp supports the model in mainline since October 25th, and Unsloth publishes compressed versions. For 12 GB cards it is not ready: the smallest version needs about 128 GB of RAM and VRAM combined, and the SSD read method strongly affects speed.
- Support landed in mainline llama.cpp on October 25th; Unsloth publishes compressed versions with a guide.
- Unsloth's guide says its smallest one-bit version wants about 128 GB of RAM and VRAM combined; 64 GB is possible but slower, with no number given.
- Closest published result: AMD R9 700 plus RTX 5060 with 128 GB RAM, about 6.5 tokens/s writing and 31 reading.
- llama.cpp maps the model file into memory and lets the OS fetch pieces from the SSD.
- Strata on a 5070 with 64 GB got 1.8 to 2.2 tokens/s with that approach, versus 4.3 to 4.9 when reading the drive directly.
Practical Checklist and Recommendations
A practical checklist ranks RAM first, then SSD speed, file choice, closing other GPU apps, and disabling thinking for quick tasks. Recommendations are given by hardware tier.
- RAM first: 32 GB makes DeepSeek on a 12 GB card a start-and-walk-away job; 64 GB opens both main routes.
- Do not buy a new GPU for this; the RTX 3060 is the reference card for both engines.
- SSD must be fast NVMe, not SATA or hard drive: 257 GB for Strata, 1.1 TB for Prometheus.
- On Strata, use the 2-bit file for code and agents; skip the 1.75-bit file for long writing; enable full quality mode when accuracy matters.
- Close other GPU-using apps, since every gigabyte borrowed comes from slower storage.
- Turn off Strata's default thinking for quick jobs; thinking for a thousand tokens costs minutes at 2 to 7 tokens/s.
- Mac builds: Strata's Mac version needs 64 GB or more of unified memory; a text-only Mac build was added recently with few numbers yet.
- With a 24 GB card and 90 GB RAM, a developer fork of Strata reports about 26 tokens/s on an RTX 4090 with DDR4 (one person, one PC).
