You may be trying to install the wrong driver. Go back to the Dell website and enter your laptop's Service Tag which should avoid the problem of getting the wrong driver for different hardware which your particular laptop may not have.
(even identical models had different hardware installed throughout their production cycle to avoid supply issues).
I also think you probably meant Inspiron 6400, not Dimension?
Using Windows' built-in "Update driver" in Device Manager will do no harm, but I would not use Drivermax or anything like it.
You may be trying to install the wrong driver. Go back to the Dell website and enter your laptop's Service Tag which should avoid the problem of getting the wrong driver for different hardware which your particular laptop may not have.
(even identical models had different hardware installed throughout their production cycle to avoid supply issues).
I also think you probably meant Inspiron 6400, not Dimension?
Using Windows' built-in "Update driver" in Device Manager will do no harm, but I would not use Drivermax or anything like it.