The original cable was a db9 to db9 cable. you might try another cable, like a db9 to usb.  The default IP address on the switch is 192.168.0.1. So you could try a telnet connection too. See you have a better success rate. www.dell.com/.../ArticleView
      Hi there! I have a Dell PowerConnect 3048 that I would like to use on my home network. For now, my network is small, but as days pass, it has been growing. The problem I am running into, even after asking Google, is that I am having a hard time finding out how to be able to configure this switch. The switch has power, and I also have the DB-9 to Ethernet console cable. For this particular switch, the console port is the DB-9 business end while the Ethernet end connects to what I presume, a computer. Again, the problem comes when I connect the console cable from the pc, to the switch and using HyperTerminal or PuTTY, I cannot seem to talk to this switch. I do not understand what I am doing wrong? From a lot of reading and watching videos, I understand that some switches have an Ethernet console port, but on this particular switch, it does not have such a port. Please walk me through on how I can talk to this switch so that I may get it configured for my home network. Kind Regards      
Dell PowerConnect 3048