ImWolf, inputting the service tag may work, but lately it seems that you have to just go with the generic brand, for example dimension 3000, and pick out the ones that are for your system, if you look in the c: drive or in a Dell folder, there should be a drivers folder, and you can get the R numbers for your drivers, but if not then you can do the following:
How To Find Drivers For An Unrecognized Device
1. Open
Device Manager (Control Panel>System>Hardware>Device Manager)
2. The hardware whose drivers are missing will appear as Unknown device, so it's easier to locate the device.
3. Right click on the unknown device and click on
Properties.
4. Under the Properties window click on
Details tab and select
Device Instance Id from the drop down box.
5. You should see a code similar to this
PCI\VEN_
8086&DEV_
27DC&SUBSYS_30868086
&REV_01\4&1E46F438&0&40F0
6. The portion of the code highlighted in
RED is the Vendor ID and the portion highlighted in
GREEN is the Device ID. In this example:
Vendor ID =
8086
Device ID =
27DC
7. Once you have obtained both the IDs, proceed to
https://www.pcilookup.com/
There you can either search for the vendor from the vendor ID or directly get information about the device along with the vendor name by searching with the device ID.