Modifying your Inspiron to work in a Latitude C/Port or C/Dock
The following instructions were created by Dell Coumminity Member Stonent.
Through voodoo, trickery and physical blocks, Dell has managed to keep Inspiron users away from the powerful features of their Latitude C/Ports and C/Docks. I guess they figured that we would never want things like using an Infrared port while docked, or having SCSI devices attached without the use of e PCMCIA card. Or even adding a PCI device. Well no longer will this hold us back..
The secret is converting your Inspiron into thinking it is a Latitude. Which is pretty easy and removing the metal hook from the port replicator.
Lets start with removing the metal hook that blocks your access. (Note: If you have an 8xx0 series system you can remove the plate on the back that blocks the slot from receiving the hook) Remove the screws (if applicable) from the bottom of the Latitude C/port or C/dock. You should then be able to remove the "lid". Now that you are inside notice where the metal hook attaches. There is a screw in the middle that holds it in place. Remove that screw and the metal hook will lift right out. If you have a C/Dock II like me, I had to remove the "motherboard" first to get at the hook. Take the metal spring too, because you don't want it rattling around inside loose. Put the screw and washer back in place and reassemble your port replicator.
Now it looks as you are all set, but if you try to dock your system in it at this point, you will recieve an error that says you have used an invalid port replicator and your computer will shut down. You now need to convert the BIOS from an Inspiron BIOS to a Latitude BIOS. First of all, you need to determine what Latitude BIOS will work on your Inspiron system. Well because I am such a nice guy, I will tell you.
3700 - Latitude CPxH BIOS
Power down and boot up undocked. As it goes into windows, it will begin a hardware detection. This is because the devices have moved around to make room for the future port replicator you are going to use. All of the drivers should still be on the system, so anything it asks for should be in C:\windows c:\winnt c:\windows\system and c:\winnt\system32 depending on your model. After a few reboots and whatnot your system should be back to normal with no (!) devices in the device manager.
If you are running Windows 95, Windows 98, Windows NT or Windows ME, check the Dell website for drivers for the port replicator and have them handy. You should run the installation program before docking.
Now boot up docked, your system will detect the new hardware in the dock and load the drivers.
Congratulations, you now have a fully working "Latitude"! From this point forward, you should use the Latitude BIOS for all future upgrades to your system.