SYSTEM process using some CPU all the time?

Does anyone have any idea how to figure out which driver is causing constant CPU usage by SYSTEM process? It used to constantly hover at around 15% but it fell down to 5% after updating Broadcom WiFi drivers. But i’d like to find out if it’s still WiFi driver or something else.
I followed some guide by Mark Rusinovitch how to find out exactly what i’m looking for but his guide only involved 32bit system. And same method doesn’t seem to work on 64bit Win7.
The thing is, when i boot system in safe mode, CPU usage actually stays at 0%. But in normal mode, constant 5% usage which is annoying and unnecessary and just eats battery since it’s a laptop.

Any ideas?

I also use laptop and in idle state it flickers around 5% 3% 2% and 0%…

so if it is on 5% constantly see processes from all users in the task manager and see what is triggering this and disable it via msconfig.

Before you give advice, it might pay for you to find out who you’re giving the advice to. ???

Especially giving advice about disabling things with msconfig as that could render the system un-bootable. :o

How about try using Windows Performance Toollit (WPT) known as xperf?
You can see the percentage of CPU Usage per modules in SYSTEM process.

Installation
http://www.msfn.org/board/topic/146919-install-the-windows-performance-tools-kit/

Usage
http://www.msfn.org/board/topic/140264-how-to-get-the-cause-of-high-cpu-usage-caused-by-apps/

Sample image attached.