Tesla P40 for Local LLMs: 24GB for ~$300, and What It Costs You (2026)

Bottom Line

• The P40 gives you 24 GB of VRAM for $240-350 used (August 2026) — the cheapest 24 GB of anything, by a factor of three against a used RTX 3090 at $1,000-1,300.
• It is a good deal on VRAM, not a good GPU. 347 GB/s of bandwidth (about a third of a 3090), no tensor cores, no usable FP16, and speed in the 40-45 tok/s range on 7B Q4 models.
• The clock is running. CUDA 13 dropped Pascal. NVIDIA’s 580-series driver branch is the last one for this card. What works today keeps working; what ships next year increasingly will not.
• Buy it for a second box: batch jobs, embeddings, a model that just needs to fit. Do not buy it as the machine your agent depends on every day — that is used-3090 territory.

What $300 Actually Buys

Per gigabyte of VRAM, the P40 costs roughly $10-15/GB against the 3090’s $42-54/GB. That ratio is the whole argument for the card, and it is a real argument: for fitting a 32B model at Q4 (about 18 GB, leaving modest context), fit is binary and the P40 fits.

The bandwidth column is the whole argument against it. Generation speed tracks memory bandwidth, and a third of the bandwidth means roughly a third of the speed on the same model, before Pascal’s missing kernel paths take their extra cut.

The Support Cliff, Precisely

This is the part most P40 guides soft-pedal, so here it is exactly:

• CUDA Toolkit 13 removed Maxwell, Pascal, and Volta support. New CUDA builds no longer target this card.
• NVIDIA has said the 580-series driver branch is the last for Pascal. After that, no new drivers — including for new kernels and new OS releases.
• FP16 was never usable (1/64th rate, a deliberate cut to protect the P100), and there are no tensor cores, so modern attention kernels either fall back or don’t run.

What this means in practice is narrower than it sounds. The P40 community runs llama.cpp and Ollama with quantized GGUF models, which are integer-heavy and maintain compatibility far behind the CUDA frontier. That path works today and will keep working on pinned drivers for years. What you lose is the frontier: vLLM, fine-tuning stacks, and anything that assumes a modern GPU will move on without you. If the MI50’s story sounds familiar, it should — the P40 is the CUDA-side version of the same trade, a couple of years behind on the same road.

The Three Taxes at Install Time

The P40 is a datacenter card, and putting one in a desktop levies three taxes no spec sheet lists:

1. Power. It takes a CPU-style 8-pin EPS feed, not a PCIe 8-pin. The connectors look similar and are keyed differently for a reason. Budget for the correct adapter and verify the pinout before powering on.
2. Cooling. It is passive. In a server, chassis fans blast air through it; in your tower, nothing does. You need a blower shroud (3D-printed or bought) or a high-static-pressure fan ducted straight through the heatsink. Skip this and the card thermal-throttles in minutes.
3. Display. There are no video outputs. You need an iGPU or a second card to see anything.

None of these is hard. All of them are why the card is $300.

Who Should Buy One

Buy the P40 if you want a second machine for batch work — overnight summarization, embeddings, testing whether a 32B model is smart enough before buying real hardware — and you enjoy the setup as part of the hobby. At $240-350 it is the cheapest admission ticket to the 24 GB tier, and for batch jobs where nobody is watching the tokens stream, a third of the speed simply means the job finishes at 4am instead of 1am.

Do not buy the P40 if it will be your only GPU or your agent’s daily host. Interactive use makes you feel every one of those missing GB/s, and building your one machine on a card whose driver branch is ending is a bad trade at any price. Spend up to a used 3090, or start at the current sub-$500 picks if the budget is fixed.

See Also

• How to buy a used RTX 3090 safely — the checklist for the upgrade path
• Best GPU under $500 for local AI — where the P40 sits among the new budget cards
• The cheapest 32GB VRAM GPU in 2026 — the MI50, the P40’s AMD-side twin
• Best local LLMs for the RTX 3090 — what the 24 GB tier actually runs
• Local LLM electricity cost break-even — 250W around the clock is not free