DeepSeek-R1-Distill-Qwen 1.5B on a GeForce RTX 4070 Ti SUPER
Yes — the unquantized weights fit with room for 128k tokens of context.
Verdict
Fits at FP16
14.7 GiB usable of 16 GB
Weights (Q4_K_M)
1.0 GiB
3.3 GiB at FP16 · 1.8B params · 6 of 6 quant rows are measured files
KV cache
28.0 KiB per token at FP16
28 layers × 2 KV heads × 128 dimensions
Speed ceiling
177 tok/s
672 GB/s ÷ bytes read per token
Every quant, against this card
Weight bytes are the size of the real published file wherever one exists — 6 of these6 rows are measured from bartowski/DeepSeek-R1-Distill-Qwen-1.5B-GGUF, the rest computed from the parameter count. Max context is what the KV cache can grow to in whatever memory the weights leave behind, capped at the 128k tokens this model was trained to address.
| Precision | Bits/weight | Weights | Source | Fits | Max context | Ceiling |
|---|---|---|---|---|---|---|
| FP16 / BF16 | 16.00 | 3.3 GiB | measured file | yes | 131,072 (model cap) | 177 tok/s |
| Q8_0 | 8.53 | 1.8 GiB | measured file | yes | 131,072 (model cap) | 316 tok/s |
| Q6_K | 6.59 | 1.4 GiB | measured file | yes | 131,072 (model cap) | 396 tok/s |
| Q5_K_M | 5.79 | 1.2 GiB | measured file | yes | 131,072 (model cap) | 442 tok/s |
| Q4_K_M | 5.03 | 1.0 GiB | measured file | yes | 131,072 (model cap) | 497 tok/s |
| Q3_K_M | 4.16 | 882 MiB | measured file | yes | 131,072 (model cap) | 580 tok/s |
What the context actually costs
The KV cache is 2 · layers · kv_heads · head_dim bytes per token per element — 2 · 28 · 2 · 128 · 2 B = 28.0 KiB. It depends on the key/value head count, not the attention-head count and not the parameter count. This model shares 2 KV heads across 12 query heads, which divides the cache by 6 against multi-head attention.
| Context | KV cache (FP16) | KV cache (8-bit) | Plus Q4_K_M weights |
|---|---|---|---|
| 4,096 | 112 MiB | 56 MiB | 1.1 GiB |
| 8,192 | 224 MiB | 112 MiB | 1.3 GiB |
| 32,768 | 896 MiB | 448 MiB | 1.9 GiB |
| 131,072 | 3.5 GiB | 1.8 GiB | 4.5 GiB |
The speed ceiling, and where it comes from
Generating one token reads every active weight from memory once. At FP16 / BF16 that is 3.3 GiB, plus a pass over the KV cache. A GeForce RTX 4070 Ti SUPER moves 672 GB/s (256-bit × 21 Gbps), so the arithmetic ceiling is 177 tok/s. Treat it as a bound, not an estimate: attention overhead, kernel launches and imperfect memory access keep real runtimes at roughly 60–80% of it, and nothing pushes past it.
Where these numbers come from
The model
- Parameters
- 1,777,088,000
- Layers
- 28
- Attention / KV heads
- 12 / 2
- Head dimension
- 128
- Trained context
- 131,072
- Checkpoint as published
- 3.3 GiB
Read from deepseek-ai/DeepSeek-R1-Distill-Qwen-1.5B. The parameter count is the Hub's own total over the tensor shapes, not a figure taken from the model's name.
The accelerator
- Memory
- 16 GB GDDR6X
- Bandwidth
- 672 GB/s
- Bus
- 256-bit × 21 Gbps
- Assumed usable
- 92% → 14.7 GiB
Capacity and bandwidth from the vendor's specification. The bandwidth figure is checked against the bus width and data rate it derives from. The usable fraction is an assumption, not a spec: a driver context, compute workspace and any attached display come out of the same pool before a weight is loaded.
Questions this pairing answers
How much VRAM does DeepSeek-R1-Distill-Qwen 1.5B need?
3.3 GiB for the weights at FP16 — 1.8B parameters at two bytes each — and 1.0 GiB at Q4_K_M. The KV cache is on top of that and is not a fixed number: this model spends 28.0 KiB per token of context, so 8,192 tokens costs a further 224 MiB. A GeForce RTX 4070 Ti SUPER makes 14.7 GiB of its 16 GB available on the assumption below.
Can a GeForce RTX 4070 Ti SUPER run DeepSeek-R1-Distill-Qwen 1.5B?
Yes — the unquantized weights fit with room for 128k tokens of context. That is the weights and the KV cache together, against 14.7 GiB of usable memory.
How fast will DeepSeek-R1-Distill-Qwen 1.5B run on a GeForce RTX 4070 Ti SUPER?
No faster than 177 tokens/second at FP16 / BF16, and in practice below it. Decoding is memory-bound: every token reads all 3.3 GiB of weights plus the cache, and this card moves 672 GB/s. That division is the ceiling — no kernel, runtime or driver beats it, and a real runtime typically reaches 60–80% of it.
Why does the context length change how much memory DeepSeek-R1-Distill-Qwen 1.5B needs?
Because the KV cache holds one key and one value vector per token, per layer, for the whole conversation, and it is allocated separately from the weights. This model has 28 layers and 2 key/value heads of 128 dimensions, shared across 12 query heads — grouped-query attention, which divides the cache by 6. That works out at 28.0 KiB per token. Parameter count tells you nothing about this number.
The same model on a different card
- GeForce RTX 5080FP16 / BF16
- GeForce RTX 5070 TiFP16 / BF16
- GeForce RTX 4080 SUPERFP16 / BF16
- GeForce RTX 4060 Ti 16GBFP16 / BF16
- GeForce RTX 3060 12GBFP16 / BF16
- GeForce RTX 4090FP16 / BF16
- GeForce RTX 3090FP16 / BF16
- Radeon RX 7900 XTXFP16 / BF16
A different model on the same card
All 62 models on GeForce RTX 4070 Ti SUPER →- SmolLM2 1.7B InstructFP16 / BF16
- Qwen2.5 1.5B InstructFP16 / BF16
- Qwen3 1.7BFP16 / BF16
- Llama 3.2 1B InstructFP16 / BF16
- TinyLlama 1.1B ChatFP16 / BF16
- MiniCPM5 1BFP16 / BF16
- Gemma 3 1B InstructFP16 / BF16
- Qwen3 0.6BFP16 / BF16
Method and limits. Weight bytes are the byte size of the real published file wherever one exists, and the model's exact parameter count times the published llama.cpp bits-per-weight where it does not. That distinction is on every row above and it matters at both ends: a sub-1B model's Q4_K_M file runs a third larger than the nominal figure because k-quants keep its embedding tables at higher precision, and an already-4-bit release cannot be quantized upward at all. The KV cache is 2 · layers · kv_heads · head_dim · bytes per token, summed over layers with each sliding-window layer capped at its window. The speed figure is a roofline bound, not a benchmark: bandwidth divided by bytes read per token, which no runtime exceeds and every runtime falls short of. The usable fraction of card memory is an assumption: 92% here, which is what this lane assumes for a dedicated card — the other class assumes 75%, so it is not one number applied to every device. That is the only assumed input on this page; every other figure is computed from the model config and the card's published specification. Nothing on this page is written by a language model. Architecture from the model's published config, fetched 2026-08-07.