A 3090 with 24GB of vram is $650 used on Facebook where I live. I think that would be a better card as you can use nvlink. Alternatively, the 4000 series cards

A 3090 with 24GB of vram is $650 used on Facebook where I live. I think that would be a better card as you can use nvlink. Alternatively, the 4000 series cards rely on the PCI express lanes for linking, so if you want to get the benefits of linking the 4000 series cards as a consumer you’ll want a Threadripper or even maybe an EPYC CPU/motherboard combo.