My brother has got a HP nc 6120 laptop, and its been about 2 years. So far it was ok, but recently what I have noticed is when I connect to the internet there is a lot of bytes being received(downloaded to the laptop), even when I am not opening internet explorer or downloading anything, that includes windows automatic update, and norton antivirus automatic update being shut off manually. The laptop has also become a little slow(has a centrino 1.6 ghz, 512 mb ram), so he decided to upgrade his hard disk from 40 gb to 120 gb. So he got a 120 gb hard disk and copied 40 gb hard disk to it using norton ghost 9, which worked very well and the laptop booted with the new drive flawlessly. But even then the unknown internet download still continues.
So he decided to get norton antivirus 2007(earlier was 2006), and installed smoothly. But when full system scan is run, the norton antivirus will scan merely about 2600 files, and will say "there is no virus/threat". When a drive is attempted to scan, Item scanned would be "1" (yes, just 1 when there is 50,000 files inside the drive) and it would say no virus threat is found. The same problem is with the source (40gb) drive as well. But If we try to scan files that are 2 levels deep, eg, system32 inside windows, it will scan all the files inside it (whereas if we right click "windows" folder and choose "scan with norton antivirus", again it would scan "0" items and would say "no virus threat detected".
So what could be the problem? How could I get the laptop running faster, and there would be no (or minimum) data transfer when the internet connection is idle). Please Help.