did you even read anything on the FAQ sheet on reinstalling your os on a Dell??
no, you will not install all, nss = notebook (laptop) system software
ethernet is network driver, audio is under audio, video is under video, and I am not sure what a pci modem driver is, but the instructions below on finding an unknown driver will help, you will install the drivers that are on your laptop, if two drivers (or more) are available, then you will see what is installed on your pc, not all of the same type of pc's have the same drivers installed.
not sure what a driver UPGRADE section is, you want the drivers downloads section, what is your service tag number??
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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
http://pcidatabase.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.
8. Then from there you can go directly to the hardware manufactureres website and get the driver.
ORDER FOR DELL INSTALL DRIVERS
Desktop System Software or Notebook System Software
Chipset or SMBus driver
Processor Driver (if applicable)
Video
Audio (sound)
Input Drivers (keyboard/mouse)
Modem
Network Card
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http://en.community.dell.com/support-forums/desktop/f/3514/t/19281817.aspx
how to find your dell sata drivers
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