surogate · text

Surogate-3.5-2B

surogate/Surogate-3.5-2B

Surogate-3.5-2B at Q4_K_M is exactly 1,598,229,728 bytes (1.49 GiB / 1.60 GB) — an effective 4.595 bits per weight, not the nominal 4. Its KV cache at 32K is 0.38 GiB.

From the file· summed from 1 file(s)From the file· KV per layer
Parameters
2.8B
Architecture
qwen35
24 layers
Context
262,144
native (config.json)
License
apache-2.0

Shipped quantizations

exact bytes, summed from published files
QuantSizeExact bytesEffective bpwTensorsPublisher
Q2_K1.08 GiB1,157,362,9123.327mradermacher
I1-Q2_K1.08 GiB1,157,363,1683.327mradermacher
Q3_K_S1.18 GiB1,264,871,6483.636mradermacher
I1-Q3_K_S1.18 GiB1,264,871,9043.636mradermacher
I1-IQ3_S1.21 GiB1,295,927,7763.726mradermacher
I1-IQ3_M1.22 GiB1,304,840,6723.751mradermacher
Q3_K_M1.25 GiB1,346,324,7043.871mradermacher
I1-Q3_K_M1.25 GiB1,346,324,9603.871mradermacher
Q3_K_L1.32 GiB1,413,826,7844.065mradermacher
I1-Q3_K_L1.32 GiB1,413,827,0404.065mradermacher
I1-IQ4_XS1.40 GiB1,498,652,1284.309mradermacher
IQ4_XS1.40 GiB1,504,550,1124.325mradermacher
I1-Q4_01.42 GiB1,525,165,5364.385mradermacher
Q4_K_S1.43 GiB1,532,374,2404.405mradermacher
I1-Q4_K_S1.43 GiB1,532,374,4964.405mradermacher
I1-IQ4_NL1.45 GiB1,552,035,2964.462mradermacher
Q4_K_M1.49 GiB1,598,229,7284.595mradermacher
I1-Q4_K_M1.49 GiB1,598,229,9844.595mradermacher
I1-Q4_11.53 GiB1,644,187,1044.727mradermacher
Q5_K_S1.64 GiB1,765,567,7125.076mradermacher
I1-Q5_K_S1.64 GiB1,765,567,9685.076mradermacher
Q5_K_M1.68 GiB1,804,422,3685.188mradermacher
I1-Q5_K_M1.68 GiB1,804,422,6245.188mradermacher
Q6_K1.88 GiB2,023,502,0485.817mradermacher
I1-Q6_K1.88 GiB2,023,502,3045.817mradermacher
Q8_02.44 GiB2,617,019,6167.524mradermacher
F164.58 GiB4,914,506,97614.129mradermacher

KV cache by context

computed per layer
ContextKV cache (f16)Flat formulaOverstated byFull / windowed / recurrent
4,0960.05 GiB0.19 GiB4.00×6 / 0 / 18
8,1920.09 GiB0.38 GiB4.00×6 / 0 / 18
16,3840.19 GiB0.75 GiB4.00×6 / 0 / 18
32,7680.38 GiB1.50 GiB4.00×6 / 0 / 18
65,5360.75 GiB3.00 GiB4.00×6 / 0 / 18
131,0721.50 GiB6.00 GiB4.00×6 / 0 / 18

18 of 24 layers use linear attention, which keeps a fixed-size recurrent state instead of a per-token cache. Those layers do not grow with context at all — treating them as ordinary attention, as a flat formula does, overstates this model's cache by roughly 4.0× at long context.

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 1.46 GiB. The real file is 1.49 GiB, because a quantization is a mixture and some tensors are always kept at higher precision.

Architecture

from config.json
Layers
24
Attention heads
8
KV heads
2
Head dim
256
Hidden size
2048
Vocab
248,320
Sliding window
none
SWA period
MLA
no
Experts
Experts per token
use_sliding_window

Questions people ask

How much VRAM does Surogate-3.5-2B need?
Q4_K_M is exactly 1,598,229,728 bytes (1.49 GiB) in weights. Add the KV cache, which depends on your context length, plus roughly half a gigabyte of runtime overhead.
How large is Surogate-3.5-2B's KV cache?
0.38 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 Surogate-3.5-2B 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.