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magnum-v4-27b

anthracite-org/magnum-v4-27b

magnum-v4-27b at Q4_K_M is exactly 16,645,381,728 bytes (15.50 GiB / 16.65 GB) — an effective 4.891 bits per weight, not the nominal 4. Its KV cache at 32K is 6.56 GiB, not the 11.50 GiB a flat formula predicts.

From the file· summed from 1 file(s)From the file· KV per layer
Parameters
27.2B
Architecture
gemma2
46 layers
Context
8,192
native (config.json)
License
gemma

Shipped quantizations

exact bytes, summed from published files
QuantSizeExact bytesEffective bpwTensorsPublisher
IQ2_XS7.82 GiB8,399,715,9362.468bartowski
IQ2_S8.06 GiB8,652,160,6082.542bartowski
IQ2_M8.75 GiB9,398,877,7922.762bartowski
Q2_K9.73 GiB10,449,575,5203.070bartowski
Q2_K_L10.00 GiB10,735,271,5203.154bartowski
IQ3_XS10.76 GiB11,550,629,4723.394bartowski
Q3_K_S11.33 GiB12,169,059,9363.576bartowski
IQ3_M11.60 GiB12,454,829,6643.659bartowski
Q3_K_M12.50 GiB13,424,647,7763.945bartowski
Q3_K_L13.52 GiB14,519,361,1204.266bartowski
IQ4_XS13.80 GiB14,814,420,5764.353bartowski
Q4_014.60 GiB15,681,461,8564.608bartowski
Q4_K_S14.66 GiB15,739,264,6084.625bartowski
Q4_K_M15.50 GiB16,645,381,7284.891bartowski
Q4_K_L15.77 GiB16,931,077,7284.975bartowski
Q5_K_S17.59 GiB18,884,206,1765.549bartowski
Q5_K_M18.08 GiB19,408,117,3445.703bartowski
Q5_K_L18.34 GiB19,693,813,3445.787bartowski
Q6_K20.81 GiB22,343,523,9366.565bartowski
Q6_K_L21.08 GiB22,629,219,9366.649bartowski
Q8_026.95 GiB28,937,387,6168.502bartowski
F162 shards50.72 GiB54,462,021,18416.002bartowski

KV cache by context

computed per layer — this model uses sliding-window attention
ContextKV cache (f16)Flat formulaOverstated byFull / windowed / recurrent
4,0961.44 GiB1.44 GiB23 / 23 / 0
8,1922.25 GiB2.88 GiB1.28×23 / 23 / 0
16,3843.68 GiB5.75 GiB1.56×23 / 23 / 0
32,7686.56 GiB11.50 GiB1.75×23 / 23 / 0
65,53612.31 GiB23.00 GiB1.87×23 / 23 / 0
131,07223.81 GiB46.00 GiB1.93×23 / 23 / 0

23 of 46 layers cache only a 4,096-token window rather than the full context, on a period of 2. Figures assume the default configuration; --swa-full disables the saving entirely.

Compare with

same modality, comparable size

Will it run on your card?

full quant x context sweep

Why other calculators give a different number

A parameters × bits ÷ 8 estimate puts Q4_K_M at roughly 14.26 GiB. The real file is 15.50 GiB, because a quantization is a mixture and some tensors are always kept at higher precision. The larger discrepancy is the cache: a flat formula gives 11.50 GiB at 32K context where the real figure is 6.56 GiB, because most of this model's layers cache a fixed window rather than the whole context.

Architecture

from config.json
Layers
46
Attention heads
32
KV heads
16
Head dim
128
Hidden size
4608
Vocab
256,000
Sliding window
4096
SWA period
2
MLA
no
Experts
Experts per token
use_sliding_window

Questions people ask

How much VRAM does magnum-v4-27b need?
Q4_K_M is exactly 16,645,381,728 bytes (15.50 GiB) in weights. Add the KV cache, which depends on your context length, plus roughly half a gigabyte of runtime overhead.
How large is magnum-v4-27b's KV cache?
6.56 GiB at 32K context with an f16 cache, computed per layer. Quantizing the cache to q8_0 roughly halves it, which is often the difference between a context length fitting and not.
Which quantization of magnum-v4-27b should I use?
Q4_K_M is the usual default. Pick the largest quantization that fits your card at the context you actually need — the table above gives exact sizes for every one published.