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Computed

Hermes 4.3 36B on a Jetson AGX Orin (64GB)

Yes, quantized. Q8_0 is the largest that fits, leaving room for 49k tokens of context.

Verdict

Q8_0

48.0 GiB usable of 64 GB

Weights (Q4_K_M)

20.3 GiB

67.3 GiB at FP16 · 36.2B params · 1 of 6 quant rows are measured files

KV cache

256.0 KiB per token at FP16

64 layers × 8 KV heads × 128 dimensions

Speed ceiling

5 tok/s

204.8 GB/s ÷ bytes read per token

Every quant, against this card

Weight bytes are the size of the real published file wherever one exists — 1 of these6 rows are measured from the published checkpoint, 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 512k tokens this model was trained to address.

48.0 GiB usableFP16 / BF16 · 67.3 GiBQ8_0 · 35.8 GiBQ6_K · 27.6 GiBQ5_K_M · 23.9 GiBQ4_K_M · 20.3 GiBQ3_K_M · 16.5 GiB
Bars are the weight bytes at each precision; the dashed line is the usable memory of a Jetson AGX Orin (64GB). Drawn from the computed byte counts, not sketched.
PrecisionBits/weightWeightsSourceFitsMax contextCeiling
FP16 / BF1616.0067.3 GiBmeasured file−19.3 GiB2.0 tok/s offloaded
Q8_08.5035.8 GiBnominalyes50,0835 tok/s
Q6_K6.5627.6 GiBnominalyes83,5256 tok/s
Q5_K_M5.6723.9 GiBnominalyes98,8677 tok/s
Q4_K_M4.8320.3 GiBnominalyes113,3479 tok/s
Q3_K_M3.9116.5 GiBnominalyes129,20610 tok/s

What the context actually costs

The KV cache is 2 · layers · kv_heads · head_dim bytes per token per element — 2 · 64 · 8 · 128 · 2 B = 256.0 KiB. It depends on the key/value head count, not the attention-head count and not the parameter count. This model shares 8 KV heads across 80 query heads, which divides the cache by 10 against multi-head attention.

ContextKV cache (FP16)KV cache (8-bit)Plus Q4_K_M weights
4,0961.0 GiB512 MiB21.3 GiB
8,1922.0 GiB1.0 GiB22.3 GiB
32,7688.0 GiB4.0 GiB28.3 GiB
131,07232.0 GiB16.0 GiB52.3 GiB

The speed ceiling, and where it comes from

Generating one token reads every active weight from memory once. At Q8_0 that is 35.8 GiB, plus a pass over the KV cache. A Jetson AGX Orin (64GB) moves 204.8 GB/s, so the arithmetic ceiling is 5 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
36,151,104,512
Layers
64
Attention / KV heads
80 / 8
Head dimension
128
Trained context
524,288
Checkpoint as published
67.3 GiB

Read from NousResearch/Hermes-4.3-36B. 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
64 GB LPDDR5 unified
Bandwidth
204.8 GB/s
Assumed usable
75% → 48.0 GiB

Capacity and bandwidth from the vendor's specification. The usable fraction is an assumption, not a spec: unified memory is shared with the OS and the display, and the GPU working-set cap is raisable on Apple silicon with `sudo sysctl iogpu.wired_limit_mb`.

Questions this pairing answers

How much VRAM does Hermes 4.3 36B need?

67.3 GiB for the weights at FP16 — 36.2B parameters at two bytes each — and 20.3 GiB at Q4_K_M. The KV cache is on top of that and is not a fixed number: this model spends 256.0 KiB per token of context, so 8,192 tokens costs a further 2.0 GiB. A Jetson AGX Orin (64GB) makes 48.0 GiB of its 64 GB available on the assumption below.

Can a Jetson AGX Orin (64GB) run Hermes 4.3 36B?

Yes, quantized. Q8_0 is the largest that fits, leaving room for 49k tokens of context. That is the weights and the KV cache together, against 48.0 GiB of usable memory.

How fast will Hermes 4.3 36B run on a Jetson AGX Orin (64GB)?

No faster than 5 tokens/second at Q8_0, and in practice below it. Decoding is memory-bound: every token reads all 35.8 GiB of weights plus the cache, and this card moves 204.8 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 Hermes 4.3 36B 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 64 layers and 8 key/value heads of 128 dimensions, shared across 80 query heads — grouped-query attention, which divides the cache by 10. That works out at 256.0 KiB per token. Parameter count tells you nothing about this number.

The same model on a different card

A different model on the same card

All 62 models on Jetson AGX Orin (64GB) →

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: 75% here, which is what this lane assumes for unified memory, where the OS and window server share the same pool — the other class assumes 92%, 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.