I'm looking for info about long PCIe ribbon cables + riser cards. By "long," I mean on the order of 3 - 4 feet. I've never seen them this long, so it's a two-part question: do they exist? assuming they do, would there be performance downsides (and how significant)?
I've googled+read a lot, but most conversations focus on normal-length cables and conclusions don't seem very… reliable/well-founded.
For context, I am planning a nonstandard layout where the GPU+other pcie components will be positioned away from the motherboard. Not literally four feet away, but I am considering cable routing, ease of maintenance, and so forth.
thanks!