VRAM tier ladder for local LLMs in 2026 at Q4_K_M: 8GB runs 7-8B dense models (Qwen3-8B is a 5.03GB file) plus small-active MoE via RAM offload, 12GB runs 8B plus 14B, 16GB runs 14B plus gpt-oss-20B, 24GB is the sweet spot up to a 27-32B dense model (Gemma-3-27B Q4_K_M is 16.55GB), and 48GB-plus runs a dense 70B needing about 45-50GB.

Updated July 3, 2026 · file sizes verified against official Hugging Face model cards and GGUF repo listings.

“What’s the best model I can actually run on my card?” is the most-asked question in local AI, and it resets every time a new GPU or model drops. The answer is almost always decided by one number: VRAM. Get the tier right and a local LLM is fast and private; get it wrong and you’re either offloading to system RAM at a crawl or running a model too small to be useful. Here’s the 2026 map, tier by tier, with real GGUF file sizes and the memory math behind them.

TL;DR · What fits your card at Q4_K_M

  • 8GB (3060 8GB / 4060 / 5060): a 7-8B dense model like Qwen3-8B (5.03GB file). Add 32GB system RAM and a small-active MoE model can offload to RAM and run above its weight.
  • 12GB (3060 12GB / 5070): an 8B with long context, or a 14B at Q4.
  • 16GB (4060 Ti 16GB / 4080 / 5080): a 14B comfortably, plus gpt-oss-20B (built to run in 16GB). A dense 27B spills to RAM here.
  • 24GB (3090 / 4090 / 7900 XTX): the sweet spot. A 27B dense (Gemma-3-27B Q4_K_M is 16.55GB) with context, or a 32B.
  • 48GB+ (2x 24GB / workstation / big unified memory): the only home path to a dense 70B (needs ~45-50GB).

Rule of thumb: total memory = weights (set by quant) + KV cache (grows with context) + compute buffers (~fixed). Default to Q4_K_M and match the model to the tier.

The rule of thumb: weights + KV cache + overhead

Total VRAM for inference breaks into three parts, and it helps to think about all three rather than a single number. The primary llama.cpp discussion on memory estimation lays it out cleanly: model data (the weights, fixed by quantization), a KV cache that grows with how many tokens of context you hold, and compute buffers that are roughly fixed. In its worked example, gpt-oss-20B needs 12.0GB of weights + 2.7GB of compute buffers + roughly 0.2GB of KV cache per 8,192 tokens of context — about 14.9GB at 8k, ~15.5GB at 32k, and ~17.9GB at the full 131,072 tokens — the same model, heavier purely from a longer context window. That KV-cache creep is the single most common reason a model that “fits” on paper still runs out of memory in practice.

For the weights themselves, the shorthand is:

  • ~2 GB per billion parameters at FP16 (full precision).
  • ~0.5 GB per billion at 4-bit, then add headroom for the KV cache and compute buffers on top.

One nuance worth internalizing: Q4_K_M isn’t true 4-bit. It’s mixed precision averaging about 4.83 bits per weight, so real GGUF files run a little larger than the clean 0.5 GB/B estimate — but it’s the everyday default, roughly half the memory of FP16 for a small quality drop. That’s why the tables below quote actual file sizes rather than the estimate. For a given card, fitting a bigger model at Q4_K_M usually beats a smaller one at Q8.

There’s one more concept that reshaped the 2026 tiers: Mixture-of-Experts (MoE). An MoE model activates only a slice of its parameters per token, so it computes like a small model but must still fit like a large one. OpenAI’s gpt-oss-20b card states 21B total parameters with only 3.6B active, natively MXFP4-quantized, and “designed to run within 16GB of memory.” Meta’s Llama 4 Scout card is starker: 17B active but 109B total across 16 experts — so its VRAM footprint is 70B-class despite the tiny active count. The takeaway for fit: MoE needs total params in memory, not active. The escape hatch is that llama.cpp can offload the inactive expert layers to system RAM (--n-cpu-moe), keeping the small active set on a modest GPU.

For an exact figure including your context length, run the numbers through the LLM VRAM Calculator; for how fast it’ll generate, the LLM Speed Calculator.

The tiers (all at Q4_K_M unless noted)

VRAM tier ladder for local LLMs, 2026
Real GGUF file sizes at Q4_K_M · add KV cache + overhead on top
VRAMExample cardsComfortable pickQ4_K_M file size (anchor)
8 GBRTX 3060 8GB, 4060, 5060Qwen3-8B (dense)Qwen3-8B = 5.03 GB
12 GBRTX 3060 12GB, 50708B long-context, or a 14BQwen3-8B Q8_0 = 8.71 GB
16 GB4060 Ti 16GB, 4080, 508014B, or gpt-oss-20B (MoE)gpt-oss-20B ~14.9 GB @ 8k ctx
24 GBRTX 3090, 4090, 7900 XTX27B dense, up to a 32BGemma-3-27B = 16.55 GB
32 GBRTX 509027-32B at higher quant / long ctx27B at Q6/Q8 + context
48 GB+2x 24GB, workstation, unifiedDense 70BLlama-3.3-70B = 42.52 GB
techfuelhq.com · July 2026 · sizes from bartowski GGUF repo listings

8 GB — entry (RTX 3060 8GB, 4060, 5060)

A 7-8B dense model. Qwen3-8B is a dense 8.2B model per its official card, and the bartowski Qwen3-8B GGUF listing puts Q4_K_M at 5.03 GB; with the KV cache and overhead it lands ~6-7 GB, comfortable at moderate context. This is the fast-8B-chat-and-coding tier.

The change since 2025 is the MoE-offload path. A small-active MoE model (like gpt-oss-20B, 3.6B active) keeps its active layers on the 8GB card and pushes the rest to system RAM via --n-cpu-moe, so with 32GB of system RAM an 8GB card can run models it could never fit whole. It’s slower than pure-GPU, but usable — and it’s the community’s default trick for stretching an 8GB card in 2026.

12 GB — comfortable small (RTX 3060 12GB, 5070)

8B with room for long context, or a 14B at Q4. The extra 4GB over the 8GB tier mostly buys KV-cache headroom: you can hold a much longer context on an 8B, or step up to a dense 14B like Phi-4 (14B, though note its 16K context is short next to the Qwen/Gemma peers). The 3060 12GB is a genuinely good LLM card for its price precisely because capacity, not raw speed, decides what fits here.

16 GB — the mid tier (RTX 4060 Ti 16GB, 4080, 5080)

A 14B comfortably, plus gpt-oss-20B. OpenAI’s gpt-oss-20b is explicitly “designed to run within 16GB of memory” — it’s an MoE with only 3.6B active params, natively MXFP4-quantized, about 14.9GB total at 8k context (rising to ~15.5GB at 32k) per the llama.cpp worked example. Cap the context to stay inside 16GB. A dense 27B does not fit here and spills to system RAM, which collapses throughput, so treat a 16GB card as a strong 14B / MoE-20B machine rather than a 27B one.

24 GB — the sweet spot (RTX 3090, 4090, 7900 XTX)

A 27B dense model, up to a 32B. Gemma-3-27B-it is a dense 27B with a 128K context window per its card, and the bartowski Gemma-3-27B GGUF listing puts Q4_K_M at 16.55 GB, leaving real headroom for KV cache. Mistral-Small-3.2-24B is another dense pick that fits here. This is the best single-card tier for serious local work. What it can’t do comfortably is a dense 70B at Q4 — that needs ~45-50GB.

32 GB — headroom (RTX 5090)

A 27-32B at higher quant (Q5/Q6) or with a long context, and gpt-oss-20B with room to spare. This is the tier where a dense 27B stops spilling under real workloads and you can run it productively without fighting for every megabyte. A dense 70B at Q4 (~45-50GB) still doesn’t fit a single 32GB card — you’d be offloading — but for a comfortable 27B or several smaller models at once, this is plenty.

48 GB+ — the 70B club (2x 24GB, workstation cards, big unified memory)

A dense 70B at Q4_K_M needs roughly 45-50GB. The bartowski Llama-3.3-70B GGUF listing puts Q4_K_M weights at 42.52 GB (marked the recommended default), and KV cache plus overhead push the working total higher. So the paths are: two 24GB GPUs (48GB), a 48GB-or-larger workstation card, or a large unified-memory machine (Apple Silicon or similar) that treats system RAM as model memory and trades raw speed for capacity. The genuinely huge MoE models — DeepSeek-V3.1 at 671B total (37B active) — are data-center territory, useful mainly as the ceiling reference: even at low quant, the total must fit.

The models worth running in 2026

The first-party-confirmed open-weights lineup, by class:

  • ~4B: Qwen3-4B (dense, 4.0B) and Gemma 3 4B — both fit even 4-6GB cards; Qwen3-4B Q4_K_M is 2.50 GB per its GGUF listing.
  • 7-9B: Qwen3-8B (dense, 8.2B) — the 8GB workhorse.
  • 12-14B: Phi-4 (dense, 14B) and Gemma 3 12B.
  • 24-32B: Mistral-Small-3.2-24B and Gemma-3-27B, both dense — the 24GB-tier models.
  • MoE: gpt-oss-20b (21B total / 3.6B active, runs in 16GB) and Llama 4 Scout (17B active / 109B total).

What changed since 2025 — the freshness moat: the Gemma 3 family ships in 1B/4B/12B/27B with 128K context on the larger sizes, gpt-oss brought a genuinely 16GB-friendly MoE, and Meta’s Llama 4 moved to native MoE. Qwen’s newer generations are live too — the Qwen3.5-27B and Qwen3.6-27B cards are 27B-class multimodal models (image-text-to-text) using a hybrid attention + sparse-MoE architecture, with a 262K native context window — a real KV-cache consideration on top of the weights, and a different fit profile than the plain dense text models above. Beyond that, community users on the low-VRAM tiers increasingly reach for small-active-param MoE models offloaded to RAM as the way to run bigger-feeling models on modest cards; treat the newest community model names as usage signal and verify the exact card before you commit VRAM to it.

A useful pattern holds across all of them: MoE models punch above their size for speed because only a few billion parameters activate per token — but they still occupy their full size in memory, so plan the fit around total params, not active.

Fit is half the question — speed is the other

A model fitting in VRAM doesn’t mean it runs fast. Generation speed is bound by memory bandwidth (each token reads the active weights once), so a big model on a modest card can fit yet feel sluggish, and the same reason is why a dedicated GPU beats CPU or unified memory on throughput even when all three technically “fit” the model. Check both before you commit to a model or a card: the VRAM calculator for fit and the speed calculator for tokens/sec. And if you’re building around a specific card, the single-RTX-5060 local-LLM walkthrough shows the full setup end to end, with real tokens/sec on one card, and the $1,000 local-AI workstation build pairs a parts list to the 16GB tier with the cloud-vs-local cost math. For the bigger picture beyond chat models — image generation, speech, and coding assistants — see the self-hosted AI stack overview.

Bottom line

For most homelab GPUs, the practical pick is simple: an 8B at Q4_K_M on 8-12GB cards (with a small-active MoE offloaded to system RAM when you want more), a 14B-20B on 16GB, and a 27-32B at Q4_K_M on a 24GB card — the single-card sweet spot. Reach for 48GB+ only when a dense 70B is genuinely worth the cost and complexity. Match the model to the VRAM tier, remember that weights + KV cache + overhead all count, default to Q4_K_M, and you’ll get fast, private inference without fighting your hardware.

Model classes, parameter counts, and context windows verified against official Hugging Face model cards (Qwen3-4B/8B, Gemma-3-27B, Phi-4, Mistral-Small-3.2-24B, gpt-oss-20b, Llama-4-Scout, DeepSeek-V3.1, Qwen3.5/3.6-27B). GGUF file sizes are actual repo listings from the bartowski quant repos. The weights + KV-cache + compute-buffer breakdown and the gpt-oss-20B context example are from the primary llama.cpp memory-estimation discussion. No first-party benchmarks were run; for tokens/sec on a real card see the linked RTX 5060 tutorial. Current as of July 2026.

Sources and methodology

Every model name, size, and file figure above is grounded in the page that carries it — an official model card or a GGUF quant repo file listing — rather than a release announcement or a rehost.

Primary sources cited:

Email corrections to hello@techfuelhq.com.

Frequently asked questions

What LLM can the RTX 4090 run?
A 24GB RTX 4090 is the local-LLM sweet spot. At Q4_K_M it runs up to a ~32B dense model with room for context (the Qwen3-32B Q4_K_M GGUF is 19.76GB per the bartowski repo listing) and handles 8B-14B models easily at higher quants. It runs a 27B dense model like Gemma 3 27B comfortably: the Gemma-3-27B-it Q4_K_M GGUF is 16.55GB per the bartowski repo listing, leaving headroom for KV cache. What a single 4090 can’t do at usable speed is a dense 70B at Q4 (that needs ~45-50GB) without offloading layers to system RAM.
What local LLM can I run on an 8GB GPU?
An 8GB card (RTX 3060 8GB, 4060, 5060) comfortably runs 7-8B dense models at Q4_K_M. Qwen3-8B at Q4_K_M is a 5.03GB file per its GGUF repo listing, so it fits with room for moderate context. The bigger 2026 shift is Mixture-of-Experts models with a tiny active-parameter count: because only a few billion params compute per token, you can keep those active layers on the 8GB card and offload the rest to system RAM (llama.cpp exposes this as –n-cpu-moe), which lets an 8GB card punch above its weight if you have 32GB of system RAM. For pure on-GPU work, though, 8GB is the fast-8B-chat tier, not the 20B+ tier.
How much VRAM does a 70B LLM need?
A dense 70B at Q4_K_M needs roughly 45-50GB of memory including overhead. The Llama-3.3-70B-Instruct Q4_K_M GGUF is 42.52GB of weights alone per the bartowski repo listing, and the KV cache and compute buffers push the working total higher, especially at long context. That exceeds any single consumer GPU, so the realistic options are two 24GB cards (2x 3090/4090 = 48GB), a workstation card with 48GB or more, or a large unified-memory machine that trades raw speed for capacity. Full-precision FP16 is far worse (~140GB), which is why 4-bit is the default.
Is the RTX 3060 better than the 4060 for LLMs?
For LLMs, the RTX 3060 12GB is often the smarter buy despite being the older, slower card, because VRAM capacity decides which models fit and the 4060 usually ships with only 8GB. 12GB lets you run a 14B at Q4 or an 8B with long context; 8GB caps you at 7-8B or forces heavy offload. The 4060 is faster per token when a model fits both cards, but on this workload capacity beats raw speed: a model that fits the 3060’s 12GB and spills off the 4060’s 8GB will feel far faster on the 3060.
Is Q4_K_M quantization good enough, or should I run higher?
Q4_K_M is the widely-recommended default. It’s mixed-precision averaging about 4.83 bits per weight (not true 4-bit), roughly half the memory of FP16, for only a small quality drop on most tasks, which is why it’s called the everyday sweet spot. Go higher (Q5_K_M, Q6_K, Q8_0) only if you have spare VRAM and want the last few percent of quality; the Qwen3-8B GGUF listing shows Q4_K_M at 5.03GB rising to Q8_0 at 8.71GB, so the higher quants cost real memory. Go below Q4 only when you’re desperate to fit a bigger model. For a given card, fitting a bigger model at Q4_K_M usually beats a smaller model at Q8.
Do I even need a GPU to run a local LLM?
No, but a GPU makes it fast. A CPU with enough system RAM can run small models at readable speed, and unified-memory machines (Apple Silicon and similar) treat system RAM as usable model memory, which is why a 64GB unified box can host models that would need a very expensive multi-GPU rig. The tradeoff is generation speed: inference is bound by memory bandwidth, and a dedicated GPU’s VRAM bandwidth is far higher than system RAM, so the same model runs many times faster on the GPU. For an 8B at Q4, a modern GPU is comfortable; for anything larger, VRAM is what makes it usable.
What are the best local LLMs to run in 2026?
The dependable, first-party-confirmed open-weights lineup spans the tiers: Qwen3-4B (dense, 4.0B) and Gemma 3 4B for small cards; Qwen3-8B (dense, 8.2B) for 8GB; Phi-4 (dense, 14B) and Gemma 3 12B for the mid tier; Mistral-Small-3.2-24B and Gemma-3-27B (both dense) for 24GB; and on the MoE side OpenAI’s gpt-oss-20b (21B total / 3.6B active, designed to run in 16GB) and Llama 4 Scout (17B active / 109B total). Newer generations exist (Qwen’s 3.5/3.6 27B lines are live), and community users increasingly favor small-active-param MoE models for low-VRAM cards. Match the model to the tier, default to Q4_K_M, and run the exact fit through the calculator before committing.

Evidence ledger

Last updated
Methodology
This guide was written and edited by Lowell K. Wood IV in St. Louis County, MO. Specs, prices, commands, and version numbers are drawn from the official vendor, reseller, and project documentation current on the date above, and were verified before publishing. First-person hardware claims appear only where the article shows a verifiable artifact — a photo, receipt, or measurement — or links to the TechFuelHQ Open Bench Datasets. Every fact is human-verified against its cited source before publishing; AI assists with first-draft structure and source-gathering, not with the verdict. Full editorial standard: methodology.
Update log
  • 2026-07-03 — 2026 SERP-intent refresh + primary-source verify pass. Grounded every model/size figure to its official Hugging Face card or GGUF repo file listing (Qwen3-4B/8B, Gemma-3-27B, Phi-4, Mistral-Small-3.2-24B, gpt-oss-20b, Llama-4-Scout, DeepSeek-V3.1, and the bartowski GGUF listings for Qwen3-4B 2.50GB / Qwen3-8B 5.03GB / Gemma-3-27B 16.55GB / Llama-3.3-70B 42.52GB). Replaced the loose 0.5GB/B rule-of-thumb framing with the primary llama.cpp weights + KV-cache + compute-buffer breakdown (discussion 15396). Added the MoE-offload / --n-cpu-moe path for small cards and a card-centric FAQ set matching live People-Also-Ask (RTX 4090, 70B VRAM, 3060-vs-4060, do-I-need-a-GPU). Added a VRAM-tier comparison table and a visible Updated date. Community model names newer than the verified first-party roster (Qwen 3.6, Gemma 4) are attributed as community usage, not re-asserted as fact.
  • 2026-06-17 — Initial publish: rule-of-thumb + tier ladder + models + speed section.
Corrections
Spotted an error or stale price? Email hello@techfuelhq.com. Confirmed corrections are added to the update log above.

About the author

Written by Lowell K. Wood IV. Lowell builds and runs TechFuelHQ from St. Louis, Missouri, pairing thirteen-plus years of hands-on homelab, PC, server, and networking experience with cited third-party testing and first-party benchmarks on the gear he still runs. He also works ground EMS as a Nationally Registered Paramedic (NREMT).