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Best GPU for a local LLM: how to choose by VRAM

Memory decides which model a GPU can run and bandwidth decides how fast. Here is what 16, 24, 32, 48 and 96 GB cards hold, how consumer, workstation and data centre cards differ, and what to check when buying in India.

A close up of a purple heat sink on a circuit board
A close up of a purple heat sink on a circuit board

The best GPU for a local LLM is the one with enough memory (VRAM) to hold your model and its context. After that, memory bandwidth decides how fast it writes. As a rough guide at 4-bit: a 16 GB card runs models up to about 14 billion parameters, 24 to 32 GB runs 32B models, and a 70B model needs about 48 GB on one card or split over two.

Gaming speed matters much less than memory size and bandwidth.

An empty processor socket on a motherboard beside blue memory slots
Whether a model fits on the card's own memory matters more than the card's gaming speed.

Why does VRAM decide the choice?

A model runs at full speed only when its weights, its context and the runtime all fit in the card's memory. If they do not, Ollama and llama.cpp move some layers to system RAM; ollama ps then shows a CPU/GPU split, and replies slow down.

So start from the model, not the card. Ollama's 4-bit downloads give the size of the weights:

Model 4-bit download
8B (qwen3:8b) 5.2 GB
14B (qwen3:14b) 9.3 GB
32B (qwen3:32b) 20 GB
70B (deepseek-r1:70b) 43 GB

Add room for the conversation, which grows with context length and with the number of people using it at once. Our guide to how much VRAM an LLM needs has the formula and worked examples, and our glossary explains VRAM.

What does memory bandwidth add?

When a model writes, each new token needs its weights read from memory again. Arm's documentation gives the rule: tokens per second is roughly memory bandwidth divided by the bytes read per token. Two cards with the same memory can therefore differ a lot in speed.

NVIDIA's GeForce pages list the memory bus rather than bandwidth: the RTX 5090 has a 512-bit bus and the RTX 5060 Ti a 128-bit one, both with GDDR7. Data centre pages list bandwidth directly: 864 GB/s for the L40S and 4.8 TB/s for the H200. NVIDIA's DGX Spark desktop takes the other route, with 128 GB of unified memory that holds models up to 200 billion parameters but at 273 GB/s, so large models fit but write more slowly than on a fast discrete card.

Consumer, workstation or data centre card?

Memory and power from NVIDIA's spec pages. The last column is our arithmetic from the table above, not a benchmark.

Class Card Memory Power Holds at 4-bit
Consumer RTX 5060 Ti 16 GB 180 W 14B
Consumer RTX 5080 16 GB 360 W 14B
Consumer RTX 5090 32 GB 575 W 32B with a longer context
Workstation RTX PRO 4000 Blackwell 24 GB, ECC 145 W 32B, short context
Workstation RTX PRO 5000 Blackwell 48 or 72 GB, ECC 300 W 70B; 72 GB leaves room for users
Workstation RTX PRO 6000 Blackwell 96 GB, ECC 600 W (Max-Q 300 W) 70B for several users
Data centre L40S 48 GB, ECC 350 W 70B, short context
Data centre H200 141 GB up to 700 W 70B at 8-bit, many users

How they differ in practice:

  • Consumer cards are sold at retail and suit one person or a pilot. Power is high for the memory you get: the RTX 5090 needs a 1,000 W power supply for the whole system.
  • Workstation cards list ECC memory and draw much less power: the RTX PRO 4000 Blackwell has 24 GB at 145 W. They suit an office machine that runs all day.
  • Data centre cards go into rack servers. The L40S has no fans of its own and relies on the server's airflow, so it does not belong in a tower under a desk.

Check software support before you buy outside NVIDIA. Ollama supports AMD Radeon cards through ROCm v7 on Linux and Windows, and Apple M series through Metal.

Should you use two GPUs?

Two cards add their memory together: two 24 GB cards give 48 GB, enough for a 70B model at 4-bit with a short context. Ollama spreads a model across all available GPUs when it does not fit on one. vLLM uses tensor parallelism across GPUs in one server; its documentation recommends pipeline parallelism instead for cards without NVLink, such as the L40S.

The costs are power, heat, slots and complexity. Where one card with enough memory exists, it is usually the simpler build. For which server software suits several cards and many users, see Ollama vs vLLM vs llama.cpp.

Open server racks in a data centre with blue network cables and rack servers
Data centre cards such as the L40S are passively cooled and rely on the airflow of a server chassis.

Buying a GPU in India

  • Prices. NVIDIA's India product pages showed no rupee prices when we checked on 10 November 2026, so get dated quotes and compare the same card and warranty across sellers.
  • Workstation cards. NVIDIA's where-to-buy page sends buyers to OEM workstations (Dell, HP, HPE, Lenovo, Supermicro and others), to channel partners such as PNY, Leadtek and Ingram Micro, and to the NVIDIA Marketplace.
  • Data centre cards are bought inside a server, so plan the rack, cooling and power with the card.
  • Power backup. Size the UPS for the whole machine, not just the card's rated power.
  • Laptops. Check the GPU memory, not the model name. Our lab's RTX 3070 Ti laptop GPU has 8 GB, enough for an 8B model at 4-bit with a modest context.
  • Rent first. A rented cloud GPU for a week lets you test your exact model before you buy. Our comparison of paying per token or running your own server helps with the longer-term sums.

Choosing a GPU for your team

For a team, the number of people using the model at once and the length of their documents usually decide the card. Our GPU servers and AI hardware service works from your models and users to a build or a rental, then sets it up and hands over a runbook. Book a consultation.