I want to host some LLM’s locally and use more advanced models. Since new hardware is out of the question, I think I should be able to pull something off buying some yesteryear equipment on ebay etc. Did anybody attempt such a project? Does it scale horizontally? (I.e. can I connext two boxes to overcome single box slowness?)
To add some practical advice:
It depends on what you mean by more advanced models. I run Qwen3.6-27b on 48GB VRAM across 3 cards (RTX 2000e Ada), and with the recent software optimizations merged into llama.cpp (tensor parallelism & MTP) I get around 30 tokens per second in generation. I use the model through openwebui for (agentic) web research and simple Q&A mostly and I’m quite happy with what it can do.
If you want something similar, maybe look at one or two second hand V100 PCIE 32GB. Or something from the Intel Arc Pro series, if you don’t mind the software support lacking behind a bit (as in less optimized).
Also it might be worth reading into the difference of dense vs MoE models, if you’re new to that. For MoE models, if your system RAM is fast enough, it’s often viable to offload the “experts” (largest parts of such models) to RAM, reducing VRAM capacity needs. Note that server motherboards with e.g. octa-channel RAM have a huge advantage over consumer boards (making DDR4 interesting despite slower speed per module).
And to adress your last question, while I have no direct experience, I’ve seen posts online about people connecting Strix Halo or DGX Spark devices, but usually via a 10+Gbit/s switch as interconnect is crucial (except if you just want to load balance).
Self-hosting LLMs is a very fun thing to do, but also a time- and money-consuming rabbit hole. You might wanna check out the LocalLlama community over at shitjustworks.
Edit: typos