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Lab · LLM VRAM · Llama

Computed

Llama 3.2 3B Instruct memory requirements

3.2B parameters — 6.0 GiB of weights at FP16, 1.9 GiB at Q4_K_M, and 112.0 KiB of KV cache per token on top. Solved against 22 real accelerators; 22 of them can hold it.

Parameters

3.2B

3,212,749,824 exactly

Weights, Q4_K_M

1.9 GiB

6.0 GiB unquantized

KV cache

112.0 KiB

per token · 28L × 8 KV × 128

Smallest card (Q4)

8 GB

Jetson Orin Nano Super (8GB)

Weights at each precision

PrecisionBits/weightWeightsSourceNotes
FP16 / BF1616.006.0 GiBmeasured fileUnquantized. Two bytes per parameter, exactly.
Q8_08.523.2 GiBmeasured fileEffectively lossless; the usual reference point for quantized quality.
Q6_K6.582.5 GiBmeasured fileQuality loss is hard to measure on most benchmarks.
Q5_K_M5.782.2 GiBmeasured fileA middle point when Q4 fits with too little room for context.
Q4_K_M5.031.9 GiBmeasured fileThe default choice for local inference — the best size/quality knee.
Q3_K_M3.911.5 GiBnominalMeasurable quality loss. Worth it only to make a model fit at all.

Every accelerator

Largest quant that fits with at least 4k of context, the context it leaves, and the bandwidth ceiling on decode speed. Each row links to the worked page for that pairing.

AcceleratorMemoryBandwidthBest quantMax contextCeiling
Apple M3 Ultra (512GB)512 GB819 GB/sFP16 / BF16131,072111 tok/s
H200 141GB (SXM)141 GB4800 GB/sFP16 / BF16131,072652 tok/s
Apple M4 Max (128GB)128 GB546 GB/sFP16 / BF16131,07274 tok/s
H100 80GB (SXM5)80 GB3350 GB/sFP16 / BF16131,072455 tok/s
A100 80GB (SXM)80 GB2039 GB/sFP16 / BF16131,072277 tok/s
Jetson AGX Orin (64GB)64 GB204.8 GB/sFP16 / BF16131,07228 tok/s
RTX 6000 Ada Generation48 GB960 GB/sFP16 / BF16131,072130 tok/s
L40S48 GB864 GB/sFP16 / BF16131,072117 tok/s
Apple M4 Pro (48GB)48 GB273 GB/sFP16 / BF16131,07237 tok/s
A100 40GB (SXM)40 GB1555 GB/sFP16 / BF16131,072211 tok/s
GeForce RTX 509032 GB1792 GB/sFP16 / BF16131,072243 tok/s
GeForce RTX 409024 GB1008 GB/sFP16 / BF16131,072137 tok/s
Radeon RX 7900 XTX24 GB960 GB/sFP16 / BF16131,072130 tok/s
GeForce RTX 309024 GB936 GB/sFP16 / BF16131,072127 tok/s
Apple M4 (24GB)24 GB120 GB/sFP16 / BF16112,49416 tok/s
GeForce RTX 508016 GB960 GB/sFP16 / BF1681,786130 tok/s
GeForce RTX 5070 Ti16 GB896 GB/sFP16 / BF1681,786122 tok/s
GeForce RTX 4080 SUPER16 GB736 GB/sFP16 / BF1681,786100 tok/s
GeForce RTX 4070 Ti SUPER16 GB672 GB/sFP16 / BF1681,78691 tok/s
GeForce RTX 4060 Ti 16GB16 GB288 GB/sFP16 / BF1681,78639 tok/s
GeForce RTX 3060 12GB12 GB360 GB/sFP16 / BF1647,33349 tok/s
Jetson Orin Nano Super (8GB)8 GB102 GB/sQ8_026,33723 tok/s

Questions about this model

How much VRAM does Llama 3.2 3B Instruct need?

6.0 GiB for the weights at FP16 and 1.9 GiB at Q4_K_M, from an exact count of 3,212,749,824 parameters. On top of that, the KV cache costs 112.0 KiB per token of context — 896 MiB at 8k and 3.5 GiB at 32k.

What is the smallest GPU that runs Llama 3.2 3B Instruct?

Of the 22 accelerators here, the smallest that holds Q4_K_M weights is the Jetson Orin Nano Super (8GB) at 8 GB — 1.9 GiB of weights against 6.0 GiB usable, leaving room for 38k tokens. For unquantized weights you need at least a Jetson Orin Nano Super (8GB).

Why is the KV cache for Llama 3.2 3B Instruct the size it is?

Because it stores one key and one value vector per token, per layer: 28 layers × 8 KV heads × 128 dimensions × 2 (K and V) × 2 bytes = 112.0 KiB per token. Grouped-query attention shares those 8 KV heads across 24 query heads, cutting the cache by 3× against multi-head attention. None of this can be read off the parameter count.

Compare with

Method and limits. The parameter count and every architecture figure on this page are read from the model's own published config and the Hub's index over its tensor shapes, fetched 2026-08-07 — nothing here is recalled from a model's name. Weight bytes are the size of a real published file wherever one exists and the parameter count times the published llama.cpp bits-per-weight where it does not; every row says which. Speed figures are roofline bounds — memory bandwidth divided by bytes read per token — not benchmarks. Nothing on this page is written by a language model.