It's on the left side just above the power switch. It has to be a SODIMM (Laptop RAM) SD-RAM (no DDR-RAM !!) module with PC100 (PC133 is of course also working) specification.
I've added two 3100cn printer with cheap, used modules from ebay without problems.

Thank you! Took less than one minute.

Here is how I tried to install a Dell 512 MB memory module:

- switched off the printer
- removed board cover on left hand side of 3000cn, just above the power switch
- inserted memory module into slot
- switched on printer
- the LCD gave the following message "016-336 Restart Printer"
- I waited for about 5 minutes, the message did not go away
- switched off the printer, waited for 5 min
- restarted the printer
- Got the same message: "016-336" Restart Printer"
- Switched off the printer
- Removed the memory module so that printer is back to the same memory as was installed when I received it
- Switched on the power
- Printer worked

How do I add the memory module and get my printer to work? Do I need to re-install the printer driver software? Are there any specific steps that I missed in the memory install process?

I did as you said for the memory stick installation. The report still shows 64MB. I got the Rosweil 256mb PC133 from NewEgg and it fit fine. How do I get the printer to know the memory is installed.
Mark Perloe
mperloe@ivf.com

I was having the same problem, but your answer got me set up, and I didn't have any problems.

If you got to the point (in START/SETTINGS/PRINTERS) you can see on the "Options" tab the amount of memory, the only thing left is to click on the "Get information from printer" button, and then click "Apply" If the memory is installed correctly (and it's pretty hard to NOT install it correctly!), and the printer does, in fact, recognize it, the amount shown in the "Items" window will change to the new total memory. Mine went from 64M to 320M when I installed a 256M stick. If it doesn't change after doing the above, it's probably because the printer doesn't recognize the memory (Not Dell???)

Thanks for your earlier comment.

I added the memory stick that others indicated would work with the unit. I went to printer driver-options-and clicked on memory and changed it to 320 and hit apply. While this changed the indicated memory in the driver, I hit get printer information, it changes back to 64k again.

So the memory stick does not seem to be recognized. Other than rebooting the printer, do you have any idea? NEWEGG: SODIMM RSWLL|256MB PC133 RET has been recommend elsewhere on this list.

Thanks for your earlier comment.

I added the memory stick that others indicated would work with the unit. I went to printer driver-options-and clicked on memory and changed it to 320 and hit apply. While this changed the indicated memory in the driver, I hit get printer information, it changes back to 64k again.

So the memory stick does not seem to be recognized. Other than rebooting the printer, do you have any idea? SODIMM RSWLL|256MB PC133 RET has been recommend elsewhere on this list.