Dell Latitude multiple personality?

ok i have a dell latitude 110L laptop which i got through my school (ITT Tech) and about month or so ago i started having problems with the ethernet port, so i call up dell and they said they would have to order a new motherboard so i was like ok cool, well it finally gets here and someone is sent over to replace it, well he takes it apart and replaces the motherboard and put it back together and starts it up and everything goes fine on the first start up but then it wont load into windows and so the guy ran some test and came up with nothing and when he restarted the laptop i noticed it said inspiron 2200 series instead of latitude 110L and i told him and he tryed flashing the bios to fix it and couldnt so he ordered a another motherboard and the next day another guy came over and put the other new one in and it had the same thing but this time windows loaded up so ok everything is fine.....for a while and now ever since this has happend i have been having nothing but problems with it, so what i want to know is, is there any way i can fix it? cause i really need this thing for school and i tryed reinstalling windows and it didnt help at all, so is there anyway to get the old bios back or what? any info would be awsome.