Problem when adding memory to Dell Laser printer 1720dn

I just bought the Dell Laser printer 1720dn. I also purchased 128MB additional memory to add to it. I bought the memory from Dell at the same time I ordered the printer. (yea I now know I could have bought the memory cheaper elsewhere)

I set the printer up and it works great on my network at home. However, when I added the additional memory and turn the printer back on, it goes thru its startup flashing and chugging and then it just sits there with all the lights flashing at once. Couldn't get it to do anything or even ping the printer.

So logically I made sure the memory was seated properly. I did that about 6 times, had a friend try it a couple of times too. I took the memory out and everything was fine. The printer started up, worked and was normal. Finally after my last atttempt, it worked. I went into the Install Options and increased the memory value to 160MB. Everything was fine for a couple of days.

Last night I tried to turn it on so I could use it and the same problem returned, all the lights flashing at once. So I took out the additional memory and it now works fine. Any ideas on what is wrong? Is the memory bad? I've followed the instructions in the manual for adding memory, not that it's rocket science. I have added memory several times over the years so I know it can be a pain sometimes to get it seated fully.