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Computed

OLMo 2 13B Instruct on an H100 80GB (SXM5)

Yes — the unquantized weights fit with room for 4k tokens of context.

Verdict

Fits at FP16

73.6 GiB usable of 80 GB

Weights (Q4_K_M)

7.8 GiB

25.5 GiB at FP16 · 13.7B params · 6 of 6 quant rows are measured files

KV cache

800.0 KiB per token at FP16

40 layers × 40 KV heads × 128 dimensions

Speed ceiling

109 tok/s

3350 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/OLMo-2-1124-13B-Instruct-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 4k tokens this model was trained to address.

73.6 GiB usableFP16 / BF16 · 25.5 GiBQ8_0 · 13.6 GiBQ6_K · 10.5 GiBQ5_K_M · 9.1 GiBQ4_K_M · 7.8 GiBQ3_K_M · 6.3 GiB
Bars are the weight bytes at each precision; the dashed line is the usable memory of an H100 80GB (SXM5). Drawn from the computed byte counts, not sketched.
PrecisionBits/weightWeightsSourceFitsMax contextCeiling
FP16 / BF1616.0025.5 GiBmeasured fileyes4,096 (model cap)109 tok/s
Q8_08.5013.6 GiBmeasured fileyes4,096 (model cap)187 tok/s
Q6_K6.5710.5 GiBmeasured fileyes4,096 (model cap)229 tok/s
Q5_K_M5.699.1 GiBmeasured fileyes4,096 (model cap)255 tok/s
Q4_K_M4.877.8 GiBmeasured fileyes4,096 (model cap)286 tok/s
Q3_K_M3.956.3 GiBmeasured fileyes4,096 (model cap)331 tok/s

What the context actually costs

The KV cache is 2 · layers · kv_heads · head_dim bytes per token per element — 2 · 40 · 40 · 128 · 2 B = 800.0 KiB. It depends on the key/value head count, not the attention-head count and not the parameter count.

ContextKV cache (FP16)KV cache (8-bit)Plus Q4_K_M weights
4,0963.1 GiB1.6 GiB10.9 GiB

The speed ceiling, and where it comes from

Generating one token reads every active weight from memory once. At FP16 / BF16 that is 25.5 GiB, plus a pass over the KV cache. An H100 80GB (SXM5) moves 3350 GB/s, so the arithmetic ceiling is 109 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
13,716,198,400
Layers
40
Attention / KV heads
40 / 40
Head dimension
128
Trained context
4,096
Checkpoint as published
25.5 GiB

Read from allenai/OLMo-2-1124-13B-Instruct. 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
80 GB HBM3
Bandwidth
3350 GB/s
Assumed usable
92% → 73.6 GiB

Capacity and bandwidth from the vendor's specification. 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 OLMo 2 13B Instruct need?

25.5 GiB for the weights at FP16 — 13.7B parameters at two bytes each — and 7.8 GiB at Q4_K_M. The KV cache is on top of that and is not a fixed number: this model spends 800.0 KiB per token of context, so 8,192 tokens costs a further 6.3 GiB. An H100 80GB (SXM5) makes 73.6 GiB of its 80 GB available on the assumption below.

Can an H100 80GB (SXM5) run OLMo 2 13B Instruct?

Yes — the unquantized weights fit with room for 4k tokens of context. That is the weights and the KV cache together, against 73.6 GiB of usable memory.

How fast will OLMo 2 13B Instruct run on an H100 80GB (SXM5)?

No faster than 109 tokens/second at FP16 / BF16, and in practice below it. Decoding is memory-bound: every token reads all 25.5 GiB of weights plus the cache, and this card moves 3350 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 OLMo 2 13B Instruct 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 40 layers and 40 key/value heads of 128 dimensions. That works out at 800.0 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 H100 80GB (SXM5) →

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.