Gemma 4 26B-A4B IT on RTX 6000 Ada (48GB) — VRAM, KV Cache & Throughput

Gemma 4 26B-A4B IT (25.81B total, 3.8B active, Sparse MoE + GQA) uses 15.84 GiB of 4-bit weights (UD-Q4_K_XL), requiring 16.75 GiB total at 8K context and 17.22 GiB at 32K on RTX 6000 Ada (~134.9 tok/s decode).

Interactive Sizing Workbench

Full Compatibility Report →
48 GB · 960 GB/s
Fits with Safe Headroom
Measured GGUF shard size HF config.json ↗
Memory Allocation Breakdown (GiB) 16.75 GiB (17.99 GB) / 48 GiB (35%)
Model Weights: 15.84 GiB KV Cache & State: 0.35 GiB Runtime & Activation Buffers: 0.56 GiB System RAM Offload: 0 GiB
Required GPU Memory
16.75 GiB
17.99 GB (decimal)
Usable Hardware Memory
45.6 GiB
48 GB (physical)
Safe Headroom
+28.85 GiB
35% utilization
Est. Decode Throughput
~134.9 tok/s
3.8B active params
Est. Prefill Throughput
~12453 tok/s
4K Prompt TTFT: ~329 ms
Est. Cost / 1M Tokens
$0.39
Sparse MoE + GQA · Apache-2.0

Recommended Hardware for Current Configuration

Best Single GPU
Arc Pro B60 24GB (24GB)
~$599
Best Value / Used GPU
RTX 3090 (24GB)
~$750
Apple Unified Memory
Ryzen AI Max+ 395 128GB
~$1,999
Cloud From
Vast.ai · $0.19 / hr
1x RTX 3090

Production Launch Commands

llama.cpp (GGUF)
llama-server -hf unsloth/gemma-4-26B-A4B-it-GGUF:UD-Q4_K_XL \
  --ctx-size 8192 -ngl 999 --flash-attn
vLLM
vllm serve google/gemma-4-26B-A4B-it \
  --max-model-len 8192 --gpu-memory-utilization 0.92
Live Token Speed Simulator (TTFT ~329ms · ~134.9 tok/s)
[Gemma 4 26B-A4B IT · 16.75 GiB] allocated on target GPU. Prefill completed in TTFT window; streaming autoregressive tokens at memory-bandwidth-bound rate...

Cloud GPU Comparison & Rent-vs-Buy TCO

Verified public rates across RunPod, Vast.ai, Vultr, and DigitalOcean.

Verified: 2026-11-04
Purchase break-even
~26.6 months
Est. local power: $4.26 / mo
Provider Recommended Instance Total VRAM Hourly Rate Monthly at Selected Hours Billing Mode Deploy
RunPod 1x RTX 3090 (Community Cloud) 24 GB $0.22 / hr $26.75 / mo Per-second Deploy GPU ↗
Vast.ai 1x RTX 3090 (Verified Host) 24 GB $0.19 / hr $22.98 / mo Spot / On-demand Deploy GPU ↗
Vultr ($300 Free Credit*) 1x L40S 48GB (Dedicated Instance · $300 Credit*) 48 GB $1.67 / hr $203.19 / mo Hourly Deploy GPU ↗
Vultr Cloud GPU 1x L40S 48GB (Dedicated Instance) 48 GB $1.67 / hr $203.19 / mo Hourly Deploy GPU ↗
DigitalOcean 1x RTX 6000 Ada (Dedicated Instance) 48 GB $1.57 / hr $190.91 / mo Per-second Deploy GPU ↗

Rates reflect public listings on the verification date and fluctuate with regional inventory.

Fine-Tuning VRAM Requirements (QLoRA / LoRA / Full) — Gemma 4 26B-A4B IT

QLoRA (4b) Fits with Safe Headroom
18.08 GiB
Model Weights: 15.84 GiB · Gradients + Optimizer: 1.2 GiB · Act: 1.04 GiB
Recommended GPU: Arc Pro B60 24GB (24GB)
LoRA (16b) Exceeds Available GPU Memory
51.25 GiB
Model Weights: 48.07 GiB · Gradients + Optimizer: 1.8 GiB · Act: 1.38 GiB
Recommended GPU: RTX PRO 6000 Blackwell (96GB)
Full BF16 Exceeds Available GPU Memory
199.51 GiB
Model Weights: 48.07 GiB · Gradients + Optimizer: 149.02 GiB · Act: 2.42 GiB
Recommended GPU: Instinct MI325X 256GB (256GB)

Engineering Sizing Notes & Optimization Playbook

Quick Hardware Verdict

RTX 6000 Ada (48GB physical, 45.6 GiB usable) runs 4-bit (UD-Q4_K_XL) Gemma 4 26B-A4B IT at 8K context using 16.75 GiB with 28.85 GiB of safe headroom (~134.9 tok/s single-stream decode).

KV Cache & Runtime Tuning

Gemma 4 26B-A4B IT uses Sparse MoE + GQA (25.81B total, 3.8B active per token). Moving from 8K to 32K context expands FP16 KV cache from 0.35 GiB to 0.82 GiB; enabling 8-bit KV cache (llama.cpp -ctk q8_0 -ctv q8_0 or vLLM --kv-cache-dtype fp8) saves 0.41 GiB at 32K (reducing total VRAM to 16.81 GiB).

VRAM Scaling Across Context Windows (4K to 128K, 4-bit Weights)

Gemma 4 26B-A4B IT VRAM scaling from 4K to 128K context (4K: 16.66 GiB, 8K: 16.75 GiB, 32K: 17.22 GiB, 128K: 19.1 GiB) 4K 16.66 GiB (KV 0.27 GiB) 8K 16.75 GiB (KV 0.35 GiB) 32K 17.22 GiB (KV 0.82 GiB) 128K 19.1 GiB (KV 2.7 GiB) RTX 6000 Ada (48GB)
Model weights remain constant while attention KV cache grows with context length and batch size.

Quantization Precision & Memory Matrix — Gemma 4 26B-A4B IT @ 8K

Quantization Format Weights (GiB) KV Cache Total VRAM (GiB) Decode Speed Compatibility (RTX 6000 Ada) Recommended GPU Data Source
Native Weights (BF16 / FP8 / MXFP4 — Lossless) (BF16) 48.07 GiB 0.35 GiB 48.98 GiB (52.59 GB) ~49.2 tok/s Exceeds Available GPU Memory RTX PRO 6000 Blackwell (96GB) Official checkpoint size
FP8 / GGUF Q8_0 (8-bit — Near-Lossless) (Q8_0) 25.54 GiB 0.35 GiB 26.45 GiB (28.4 GB) ~95.3 tok/s Fits with Safe Headroom Radeon AI PRO R9700 32GB (32GB) Config-derived formula
GGUF Q6_K (6-bit — High Precision) (Q6_K) 21.58 GiB 0.35 GiB 22.49 GiB (24.15 GB) ~108.3 tok/s Fits with Safe Headroom Radeon AI PRO R9700 32GB (32GB) Measured GGUF shard size
GGUF Q5_K_M (5-bit — Balanced) (Q5_K_M) 19.7 GiB 0.35 GiB 20.61 GiB (22.13 GB) ~115.8 tok/s Fits with Safe Headroom Arc Pro B60 24GB (24GB) Measured GGUF shard size
Q4_K_M / UD-Q4_K_XL / AWQ (4-bit — Recommended) (UD-Q4_K_XL) 15.84 GiB 0.35 GiB 16.75 GiB (17.99 GB) ~134.9 tok/s Fits with Safe Headroom Arc Pro B60 24GB (24GB) Measured GGUF shard size
GGUF IQ4_XS (4.25-bit — Compact) (IQ4_XS) 12.66 GiB 0.35 GiB 13.57 GiB (14.57 GB) ~156.2 tok/s Fits with Safe Headroom RTX 4060 Ti 16GB (16GB) Measured GGUF shard size
GGUF Q3_K_M (3-bit — Low VRAM) (Q3_K_M) 11.85 GiB 0.35 GiB 12.76 GiB (13.7 GB) ~162.7 tok/s Fits with Safe Headroom RTX 4060 Ti 16GB (16GB) Measured GGUF shard size
GGUF UD-Q2_K_XL (2-bit — Extreme MoE) (UD-Q2_K_XL) 9.82 GiB 0.35 GiB 10.73 GiB (11.52 GB) ~181.7 tok/s Fits with Safe Headroom RTX 4060 Ti 16GB (16GB) Measured GGUF shard size

Technical Specifications & FAQ

Does Gemma 4 26B-A4B IT fit on RTX 6000 Ada (48GB)?

In 4-bit (UD-Q4_K_XL) at 8,192 context, Gemma 4 26B-A4B IT requires 16.75 GiB total GPU memory (15.84 GiB weights + 0.35 GiB KV cache + 0.56 GiB runtime buffers) against 45.6 GiB usable on RTX 6000 Ada, delivering ~134.9 tok/s decode.

How much VRAM does Gemma 4 26B-A4B IT need at 32K context?

At 32,768 context tokens, Gemma 4 26B-A4B IT (Sparse MoE + GQA) allocates 0.82 GiB for KV cache and state, bringing total 4-bit VRAM to 17.22 GiB (18.49 GB decimal).

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