Something is eating up my bandwidth...... Pls help urgent?

[ChOcoLaTe HoUse®]

Whenever I connect to Internet, something starts downloading automatically, without my consent. I can see this download activity in my Bandwidth Meter.
Because of this.... my browsing speed has miserably reduced. I cant open facebook, yahoo or anything.

Plss help..... this is my new laptop which is set to automatic Windows update..... but there's no way to confirm that my Windows update is the culprit. I dont know which app or anything else is using Internet.
Plss help. I want everything back in my control. So that nothing gets downloaded or uploaded without my permission.

(i have Windows8 64bit on Lenovo G500s)
@Bob: Thanks, i did exactly what u said.... & i found something named as "fshoster32.exe" which is consuming most of the bandwidth. I googled abt it & found that it is related to F-Secure antivirus.

I forgot to mention that, I've F-Secure Internet Security 2014 installed on my computer.... but i'm still concerned whether "fshoster32.exe" is just a regular Antivirus update... or something else.

[Bob]

This is how to check if something is eating up your bandwidth:

- Open Task Manager

- Go to the 'Performance' tab

- click on 'Resource Monitor'

- In the 'Resource Monitor' window, select the 'Network' tab

- You will find the list of 'Processes with Network Activity'

- You may select and terminate the process that you think is not necessary.

In response to 'Additional Details' - It looks like fshoster32.exe is downloading updates for your anti-virus database. This is more likely if your Windows and/or anti-virus is newly installed.

I cannot suggest terminating the process to check, as it might be harmful for the system. You might just close all browsers and other updates to see the activity of fshoster32.exe alone.

[Bobby]

It could be some kind of Virus or Trojan which is eating up your bandwidth. First scan your whole system with some good anti-virus and than see if this solve your problem if not than yes there maybe some live windows update or some background application which is consuming your bandwidth.

[Amit]

there are different ways to stop or to prevent any program from using your bandwidth others have mentioned reasons and ways to prevent it,,
well the easiest way to stop that from happening is to download a third party software called net limiter

http://www.netlimiter.com/download.php

once you run it , it shows all the program accessing your bandwidth .. you can either prevent the access from there or delete it. and here is the link for you to see how to :

https://www.youtube.com/watch?v=BYOZ5EFP4cE