[jcgrillo]

I got a well used HP Z840 with 256GB ECC DDR4 and twin Xeons ca. 2014. Then I slapped 2 AMD V640 32GB passively cooled GPUs in it with some 3D printed fan shrouds and 2 1U 15k rpm fans each. They just fit! I needed to order a quad 8pin power cable, the standard configuration has 3 6pin cables--but there's unused pins on the GPU power rail, and there are aftermarket suppliers.

72 Xeon cores

256GB ECC DDR4

64GB VRAM

$2200 total

I run it on a 20A 240V outlet to make sure the power supply can deliver enough watts, but so far it's working pretty well. The eWaste LLM rig is probably not as good value for money as a new machine, but it gets the job done cheaper (for now).

EDIT: IIRC this approach gets me more VRAM bandwidth than Strix Halo at the cost of less addressable GBs (but a lot more total system RAM), but I figured with CPU offloading that might make up for it?

ALSO EDIT: Note you can get a 128GB Strix Halo motherboard minus power supply, fans, case, etc from Framework for $2200.. that could work if you have some parts lying around.