Recently I encountered a strange problem in which a process called System (NT Kernel & System) I was using about 15 to 30 percent of the CPU on my Windows machine all the time.
In the screenshot above, the system is using a 0% CPU, which is how it should be normally. Basically, the system process hosts the kernel and driver code plus the system threads and is an essential Windows process. Do not try to kill the process or eliminate it.
Before going into technical details, this problem is usually caused by a defective or outdated hardware driver in Windows. There are a couple of things you want to check immediately:
New hardware : Recently installed some new hardware on your Windows machine? Graphics card, hard drive, sound card, TV tuner card, etc.? If so, you should go to the manufacturer's website and download the latest driver from there. If you only install the driver from the CD that comes with the new hardware, it may be outdated.
Updated driver : Did you recently update a driver and see more CPU usage after the update? Sometimes the latest drivers can also cause problems. In this case, you should try to revert the driver and see if that solves the problem.
In my case, I installed a new graphics card on my PC and installed the driver from the CD. It was not the most recent driver and, as it was a kernel mode driver, it was causing this increase in the system process.
If you cannot find out which driver is causing the problem, there is a more technical procedure you can follow to find the exact problem driver. First, download a program called KrView (Kernrate Viewer), which is a free tool from Microsoft.
It is a command line tool, so open a command prompt and then run the program without any arguments. Here is how the results should look:
Now you can see which device drivers are getting the highest number of hits in the kernel. The first one is called ntkrnlpa And it can be ignored. You want to look at the other drivers after that. In this case b57nd60x . So this driver is exactly what hardware are you wondering for?
Well, to find out, you need to download another free Microsoft tool called Process Explorer. Install it, run it and then go to the DLL view to see the loaded drivers.
As you can see, the b57nd60x.sys DLL is the driver for the Broadcom NetXtreme Gigabit Ethernet card. Candy! Now you just have to go find the updated driver for the network card and, hopefully, the peak in the CPU disappear.
Of course, the other solution in these types of cases is to simply disable that piece of hardware or remove it from your system completely if you don't need it or can't find an updated driver. Source: Technet