These are a bit mythical, finding one for sale is no small feat. I guess adding memory to some cards is a matter of completely reworking the PCB, not just swap

These are a bit mythical, finding one for sale is no small feat. I guess adding memory to some cards is a matter of completely reworking the PCB, not just swapping DRAM chips. From what I can find it has been done, both chip swaps and PCB reworks, it's just not easy to buy. Software support is of course another consideration.