I used a similar budget and build something like this:
7x RTX 3060 - 12 GB which results in 84GB Vram
AMD Ryzen 5 - 5500GT with 32GB Ram
All in a 19-inch rack with a nice cooling solution and a beefy power supply.
My costs? 1300 Euro, but yeah, I sourced my parts on ebay / second hand.
(Added some 3d printed parts into the mix:
https://www.printables.com/model/1142963-inter-tech-and-gene...
https://www.printables.com/model/1142973-120mm-5mm-rised-noc...
https://www.printables.com/model/1142962-cable-management-fu... if you think about building something similar)
My power consumption is below 500 Watt at the wall, when using LLLMs,since I did some optimizations:
* Worked on power optimizations and after many weeks of benchmarking, the sweet spot on the RTX3060 12GB cards is a 105 Watt limit
* Created Patches for Ollama ( https://github.com/ollama/ollama/pull/10678) to group models to exactly memory allocation instead of spreading over all available GPUs (This also reduces the VRAM overhead)
* ensured that ASPM is used on all relevant PCI components (Powertop is your friend)
It's not all shiny:
* I still use PCIe3 X1 for most of the cards, which limits their capability, but all I found so far (PCIe Gen4 x4 extender and bifurcation/special PCIE routers) are just too expensive to be used on such low powered cards
* Due to the slow PCIe bandwidth, the performance drops significantly
* Max VRAM per GPU is king. If you split up a model over several cards, the RAM allocation overhead is huge! (See Examples in my ollama patch about). I would rather use 3x 48GB instead of 7x 12G.
* Some RTX 3060 12GB Cards do idle at 11-15 Watt, which is unacceptable. Good BIOSes like the one from Gigabyte (Windforce xxx) do idle at 3 Watt, which is a huge difference when you use 7 or more cards. These BIOSes can be patched, but this can be risky
All in all, this server idles at 90-100Watt currently, which is perfect as a central service for my tinkerings and my family usage.
7x RTX 3060 - 12 GB which results in 84GB Vram AMD Ryzen 5 - 5500GT with 32GB Ram
All in a 19-inch rack with a nice cooling solution and a beefy power supply.
My costs? 1300 Euro, but yeah, I sourced my parts on ebay / second hand.
(Added some 3d printed parts into the mix: https://www.printables.com/model/1142963-inter-tech-and-gene... https://www.printables.com/model/1142973-120mm-5mm-rised-noc... https://www.printables.com/model/1142962-cable-management-fu... if you think about building something similar)
My power consumption is below 500 Watt at the wall, when using LLLMs,since I did some optimizations:
* Worked on power optimizations and after many weeks of benchmarking, the sweet spot on the RTX3060 12GB cards is a 105 Watt limit
* Created Patches for Ollama ( https://github.com/ollama/ollama/pull/10678) to group models to exactly memory allocation instead of spreading over all available GPUs (This also reduces the VRAM overhead)
* ensured that ASPM is used on all relevant PCI components (Powertop is your friend)
It's not all shiny:
* I still use PCIe3 X1 for most of the cards, which limits their capability, but all I found so far (PCIe Gen4 x4 extender and bifurcation/special PCIE routers) are just too expensive to be used on such low powered cards
* Due to the slow PCIe bandwidth, the performance drops significantly
* Max VRAM per GPU is king. If you split up a model over several cards, the RAM allocation overhead is huge! (See Examples in my ollama patch about). I would rather use 3x 48GB instead of 7x 12G.
* Some RTX 3060 12GB Cards do idle at 11-15 Watt, which is unacceptable. Good BIOSes like the one from Gigabyte (Windforce xxx) do idle at 3 Watt, which is a huge difference when you use 7 or more cards. These BIOSes can be patched, but this can be risky
All in all, this server idles at 90-100Watt currently, which is perfect as a central service for my tinkerings and my family usage.