1. I am in the process of retiring old PCs which still have some unfinished SETI work.
I want to move the unfinished work to newer, faster and less electricity hungry PC.
I need the space too.
2. Is there an easy/simple way to do it ?
3. LINUX and WINDOWS machines are involved. Both use NVIDIA GPU cards,
a mix of GPU models.
4. Would it be better to just ABORT the work on the older PCs ? The easy solution.

Should I take option 4 and forget about the move ? Meanwhile, I will just let the older
PCs run until they complete all queued work.

If you want to move work, you have to move the whole data directory to the new PC. The data can only run on one computer, so after the move, don't run it on the old computer as well.
You cannot merge multiple computers into one.
You cannot mix tasks registered to Windows and Linux PCs.
Windows computers have to go to new Windows computers, Linux computers have to go to new Linux computers.
Work for Nvidia GPUs can only be finished on Nvidia GPUs - but doesn't need to be the same model, as long as the application is the same and can run on the same GPU. Same for AMD GPUs.

So yes, the easiest way is to abort the work. Don't forget to report it afterwards.

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