NVIDIA Tesla P40

The Tesla P40 is the cult pick for one reason: it’s the cheapest 24GB card going. It’s an old Pascal datacentre board with no display output, passive cooling you’ll have to solve yourself, and weak half-precision maths. But 24GB for around £250 is a hard number to argue with, and that’s why homelabbers keep buying them.

The take

Buy it purely for cheap VRAM, with your eyes open about the faff. On pure £/GB it beats everything here, a used 3090 included. The catches are real, though. It’s a passive card built for server airflow, so you’ll need to bolt on a fan shroud or it’ll cook itself. It has no video output, so it can’t be your only GPU. And Pascal’s half-precision performance is poor, so it leans on quantised formats and older code paths. It’s a project, not a plug-and-play card. But the maths at the checkout is unbeatable.

What it’ll actually run

Twenty-four gigabytes runs the same big models a 3090 does on paper: a 32B at Q4 with context fits fine, and two P40s will hold a 70B at Q4. The capacity is the whole appeal, and it’s real. What you give up is speed. The 347 GB/s GDDR5 and weak FP16 mean throughput sits well below any modern 24GB card. Expect roughly 10 to 20 tokens/sec on a 13B at Q4, and slower again on bigger models. Quantised GGUF quants through llama.cpp are your friend here, since they lean on the integer and FP32 paths the P40 handles far better than half precision.

On value, nothing touches it. Around £250 for 24GB is roughly £10 per gigabyte, comfortably the best figure on this page. You’re trading speed, quiet, and convenience for the cheapest large-model capacity there is. Just budget for cooling and a second GPU for display, and treat the driver setup as part of the fun rather than a chore.

Who should buy it, and who shouldn’t

Buy it if you love a tinker and you want maximum VRAM for minimum outlay, especially for running big models slowly at home. Homelab builders adore these for exactly that. It’s the cheapest door into 70B-class models if you’ll stack two, and getting one purring is a satisfying weekend.

Skip it if you want speed, quiet, or a card that just works out of the box; the cooling job, the missing display output, and the modest pace rule it out for anyone who wants a simple life. For a few hundred more, a used 3090 gives you the same 24GB with none of the hassle and far more speed. But if the goal is the most VRAM per pound and you enjoy the build, nothing beats a P40.