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palmoteayesterday at 2:46 PM8 repliesview on HN

> If you have to ask then your GPU is too small.

What's the minimum memory you need to run a decent model? Is it pretty much only doable by people running Macs with unified memory?


Replies

gioboxyesterday at 3:02 PM

It's worth noting now there are other machines than just Apple that combine a powerful SoC with a large pool of unified memory for local AI use:

> https://www.dell.com/en-us/shop/cty/pdp/spd/dell-pro-max-fcm...

> https://marketplace.nvidia.com/en-us/enterprise/personal-ai-...

> https://frame.work/products/desktop-diy-amd-aimax300/configu...

etc.

But yes, a modern SoC-style system with large unified memory pool is still one of the best ways to do it.

jchwyesterday at 3:00 PM

32 GiB of VRAM is possible to acquire for less than $1000 if you go for the Arc Pro B70. I have two of them. The tokens/sec is nowhere near AMD or NVIDIA high end, but its unexpectedly kind of decent to use. (I probably need to figure out vLLM though as it doesn't seem like llama.cpp is able to do them justice even seemingly with split mode = row. But still, 30t/s on Gemma 4 (on 26B MoE, not dense) is pretty usable, and you can do fit a full 256k context.)

When I get home today I totally look forward to trying the unsloth variants of this out (assuming I can get it working in anything.) I expect due to the limited active parameter count it should perform very well. It's obviously going to be a long time before you can run current frontier quality models at home for less than the price of a car, but it does seem like it is bound to happen. (As long as we don't allow general purpose computers to die or become inaccessible. Surely...)

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TechSquidTVyesterday at 3:03 PM

My Mac Studio with 96GB of RAM is maybe just at the low end of passable. It's actually extremely good for local image generation. I could somewhat replace something like Nano Banana comfortably on my machine.

But I don't need Nano Banana very much, I need code. While it can, there's no way I would ever opt to use a local model on my machine for code. It makes so much more sense to spend $100 on Codex, it's genuinely not worth discussing.

For non-thinking tasks, it would be a bit slower, but a viable alternative for sure.

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layer8yesterday at 2:57 PM

It’s also doable with AMD Strix Halo.

bfivyvysjyesterday at 2:47 PM

A bit like asking how long is a piece of string.

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angoragoatsyesterday at 2:57 PM

Macs with unified memory are economical in terms of $/GB of video memory, and they match an optimized/home built GPU setup in efficiency (W/token), but they are slow in terms of absolute performance.

With this model, since the number of active parameters is low, I would think that you would be fine running it on your 16GB card, as long as you have, say 32GB of regular system memory. Temper your expectations about speed with this setup, as your system memory and CPU are multiple times slower than the GPU, so when layers spill over you will slow down.

To avoid this, there's no need to buy a Mac -- a second 16GB GPU would do the trick just fine, and the combined dual GPU setup will likely be faster than a cheap mac like a Mac mini. Pay attention to your PCIe slots, but as long as you have at least an x4 slot for the second GPU, you'll be fine (LLM inference doesn't need x8 or x16).

utilize1808yesterday at 2:51 PM

Obviously going to depend on your definition of "decent". My impression so far is that you will need between 90GB to 100GB of memory to run medium sized (31B dense or ~110B MoE) models with some quantization enabled.

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littlestymaaryesterday at 2:51 PM

No, GP is excessively restrictive. Llama.cpp supports RAM offloading out of the box.

It's going to be slower than if you put everything on your GPU but it would work.

And if it's too slow for your taste you can try the quantized version (some Q3 variant should fit) and see how well it works for you.