Can Gemma 3 12B run on RX 6800 XT 16GB?
YES — Tight Fit
Gemma 3 12B needs ~14.7 GB VRAM. RX 6800 XT 16GB has 16.0 GB. With Q4_K_M quantization, expect ~31 tok/s.
Operating mode
Choose the run profile you care about
Interactive favors responsiveness, while light API and scale-out lean harder on serving readiness. The fit stays the same, but the recommendation lens changes.
Current mode
Balanced
Balanced for general local use. Keeps the ranking neutral across personal and serving workflows.
Select quantization to explore
Fit status
Tight fit
Decode
31.2 tok/s
TTFT
6211 ms
Safe context
20K
Memory
14.7 GB / 16.0 GB
Memory breakdown
See how fast it feels
What limits this setup
This setup is broadly balanced for this model.
No major red flags
This recommendation has enough memory headroom and acceptable estimated speed for the selected workload.
Best improvement path
Performance by workload
| Workload | Grade | Fit | Decode | TTFT | Context |
|---|---|---|---|---|---|
| Chat | A | Runs well | 31.2 tok/s | 3388 ms | 20K |
| Coding | A | Tight fit | 31.2 tok/s | 6211 ms | 20K |
| Agentic Coding | F | Too heavy | 15.3 tok/s | 18438 ms | 20K |
| Reasoning | A | Tight fit | 31.2 tok/s | 7341 ms | 20K |
| RAG | F | Too heavy | 15.3 tok/s | 23047 ms | 20K |
Quantization options
How Gemma 3 12B (12B params) fits at each quantization level on RX 6800 XT 16GB (16.0 GB usable).
| Quant | Bits | VRAM | Quality | Fit |
|---|---|---|---|---|
Q2_K | 2 | 4.7 GB | Low | A78 |
Q3_K_S | 3 | 5.9 GB | Low | A79 |
NVFP4 | 4 | 6.7 GB | Medium | A80 |
Q4_K_M | 4 | 7.3 GB | Medium | A81 |
Q5_K_M | 5 | 8.6 GB | High | A81 |
Q6_KBest for your GPU | 6 | 9.8 GB | High | A81 |
Q8_0 | 8 | 12.8 GB | Very High | F0 |
F16 | 16 | 24.6 GB | Maximum | F0 |
Get started
Copy-paste commands to run Gemma 3 12B on your machine.
Run
ollama run gemma3:12bYour hardware
More models your RX 6800 XT 16GB can run
| Model | Params | Grade | Decode | Capabilities |
|---|---|---|---|---|
| 👁 Alibaba Qwen 3 14B | 14B | S | 36.3 tok/s | |
| 👁 Microsoft Phi-4-reasoning-plus 14B | 14.7B | S | 34.4 tok/s | |
| 👁 OpenAI GPT-OSS 20B | 21B | A | 33.2 tok/s | |
| 👁 Mistral Ministral 3 14B | 14B | S | 36.1 tok/s | |
| 👁 Mistral Codestral 2 25.08 | 22B | A | 12.1 tok/s |
