I can't get ubuntu, or cups, or something to tell our HPLJ 5si printer to accept one upload of our one-page newsletter and then run 310 copies. (I understand this is called "RIP once, print many.") Instead, the software uploads the page 310 times. This takes maybe 10 times as long to print the newsletter... hours and hours.

So we have to maintain two computers: a MS Windows box to print the newsletter, and an Ubuntu Linux box for everything else. Windows has no problem running the newsletter fast. If Linux could do it, we could ditch MS!

We've monkeyed with checking/unchecking the "collation" box, different drivers, setting the default copies to 310 in the management software, and so on. Nothing has worked. Does anyone know what we're doing wrong?

Make sure that you have the latest hplip package from http://linux.softpedia.com/get/Print...ing-4531.shtml. I have different HP printer hardware but had similar troubles until I got good support in HPLIP for my specific devices.

Make sure that your printer has the latest firmware that matches the requirements of the CUPS and HPLIP parts.

Another thing has to do with the way to queue the print request.
Print requests "queue a job". The job might involve several files.
Your request might ask for per-file or per-job copies and collation.
Somewhere along the chain: application --> utilities --> cups --> spooler things make decisions about when to us printer-based replication for copies and when to send extra content downline.
You'll need a printer guru to suss that out for you.

I wish I could offer more specific help.
Good luck,
~~~ 0;-Dan