>>105599390what you're thinking of affects pcie which goes up to 8ghz in 4.0.
not only are the pcie traces hundreds of times longer than anything inside a chip, and not only are the frequencies higher than anything inside the chips, but you can use a cable to go several feet out with pcie and it still works at full speed.
Now these gpus are a bunch of normal gpus connected together with what is more or less equivalent to pcie bus, but the length isn't a significant factor.