Phi-4 14B needs ~14.1 GB VRAM. RX 6900 XT 16GB has 16.0 GB. With Q4_K_M quantization, expect ~37 tok/s.
Operating mode
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
36.7 tok/s
TTFT
5270 ms
Safe context
16K
Memory
14.1 GB / 16.0 GB
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.
| Workload | Grade | Fit | Decode | TTFT | Context |
|---|---|---|---|---|---|
| Chat | S | Runs well | 36.7 tok/s | 2875 ms | 16K |
| Coding | A | Tight fit | 36.7 tok/s | 5270 ms | 16K |
| Agentic Coding | A | Runs with offload (needs ~0.6 GB host RAM) | 23.8 tok/s | 11819 ms | 16K |
| Reasoning | A | Tight fit | 36.7 tok/s | 6228 ms | 16K |
| RAG | A | Runs with offload (needs ~0.6 GB host RAM) | 23.8 tok/s | 14774 ms | 16K |
How Phi-4 14B (14B params) fits at each quantization level on RX 6900 XT 16GB (16.0 GB usable).
| Quant | Bits | VRAM | Quality | Fit |
|---|---|---|---|---|
Q2_K | 2 | 5.5 GB | Low | A81 |
Q3_K_S | 3 | 6.9 GB | Low | A82 |
NVFP4 | 4 | 7.8 GB | Medium | A83 |
Q4_K_M | 4 | 8.5 GB | Medium | A83 |
Q5_K_M | 5 | 10.1 GB | High | A83 |
Q6_KBest for your GPU | 6 | 11.5 GB | High | A82 |
Q8_0 | 8 | 15.0 GB | Very High | F0 |
F16 | 16 | 28.7 GB | Maximum | F0 |
Copy-paste commands to run Phi-4 14B on your machine.
Run
ollama run phi4Your hardware
| Model | Params | Grade | Decode | Capabilities |
|---|---|---|---|---|
 Phi-4-reasoning-plus 14B | 14.7B | S | 35 tok/s | |
 GPT-OSS 20B | 21B | A | 33.8 tok/s | |
 Codestral 2 25.08 | 22B | A | 12.3 tok/s | |
 CogVLM2 19B | 19B | A | 19 tok/s |
Yes, RX 6900 XT 16GB can run Phi-4 14B with a A grade (Tight fit). Expected decode speed: 36.7 tok/s.
Phi-4 14B (14B parameters) requires approximately 14.1 GB of memory with Q4_K_M quantization.
The recommended quantization for Phi-4 14B is Q4_K_M, which balances quality and memory efficiency.
On RX 6900 XT 16GB, Phi-4 14B achieves approximately 36.7 tokens per second decode speed with a time-to-first-token of 5270ms using Q4_K_M quantization.
For coding workloads, Phi-4 14B on RX 6900 XT 16GB receives a A grade with 36.7 tok/s and 16K context.
On RX 6900 XT 16GB, Phi-4 14B can safely use up to 16K tokens of context. The model's official context limit is 16K, but available memory constrains the safe maximum.
Paste this snippet into any page to show a live fit card.
<iframe src="https://willitrunai.com/embed/phi-4-14b-on-rx-6900-xt-16gb" width="400" height="180" frameborder="0" style="border:none;border-radius:12px;overflow:hidden;" title="Will It Run AI — fit result"></iframe>
Preview: