Hardware Interrupts causing 25% - 30% CPU usage

Though through the Process Management Software (for me is Process Hacker 2), we can suspend such crazy thread in the "system" process (in my laptop, it is acpi.sys+0x1af7c), making PC runs smoothly but unstable, the faulty is that whole system is running without the problematic ACPI support -- which can cause many unsuspected problem from System Freeze to BSOD. Probably the final cause of this annoying problem is a defective BIOS file and thus the final solution is just to flash another "good" BIOS.

I have an ASUS N43sn Laptop with i5-2410 and GT 550M, and I only have the solution of such a model. For other brands, the problem is likely to be the BIOS, but I don't know what the exact solution is.So flash an old BIOS version from your manufacture's support site just at your own risks.

Here is my experience with my ASUS N43sn.
When I flashed the latest one (which on the support site is "BIOS 414" ) , the problem always appeared ,
but since I decided to flash the original one (which called "BIOS 205" ) , the problem has just gone , and everything runs smoothly.
"Rolling back" the BIOS must add something after the orignal command,
For ASUS with winflash software, just type "winflash /nodate" at the current WinFlash directory in the Command Prompt with Administrator Rights , choose the Ver.205 BIOS downloaded from ASUS's website. At least after that my laptop calmed down again from the CRAZY System Interrupts State!

Hope this will be helpful to everyone.

Sorry for my bad English. ^_^

yaorj said:

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I have an ASUS N43sn Laptop with i5-2410 and GT 550M, and I only have the solution of such a model. For other brands, the problem is likely to be the BIOS, but I don't know what the exact solution is.So flash an old BIOS version from your manufacture's support site just at your own risks.
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Hi! Just the same case I have. It is described some posts above. I changed some motherboard chipset timings in BIOS.
Maybe you did something alike?
Bye!

Thanks to all the contributors I solved the same problem on my work PC.

My first attempt was the PCI Quadro NVS video card, which didn't work. Second attempt was the Intel 82579LM Gigabit Lan adapter, disabled the 'Wake on magic packet' and ' Wake on pattern match' functions in the Advanced tab and the Systems thread CPU usage went from 30-50% down to 5%. PC is Dell Optiplex on Windows 7 Enterprise 64bit, Core i3 2120, 4GB RAM.

Thanks again guys.

Hi all,
experienced the same problem, after awaking from hybernation, it felt down. My problem was second monitor connected through display port. When turned laptop on from the beginning, first core was steady at 60% usage, while the others were down. When disconnected displayport, it immediatelly felt down to 1% usage overall (all CPU cores summary). After reconnecting displayport, it was still down.

Hope this helps to some guys. Thank you anyway.

I have a Dell E6430S and I had the same issue, ~40% CPU hogged and the fan on all the time.
What helped me is Michaelmc's post, seems like we had the same issue.
I set the the two parameters he mentions to "Disable" and voile, fan stopped straight away

The path to use in case you are not familiar is:

Start -> Control Panel -> Device Manager -> Network Adapters
At this point, right click on the adapter you are currently using and choose properties
in the new window -> Advanced tab
and at the bottom of the left window you will see the two offending parameters

Michaelmc said:

Thanks to all the contributors I solved the same problem on my work PC.

My first attempt was the PCI Quadro NVS video card, which didn't work. Second attempt was the Intel 82579LM Gigabit Lan adapter, disabled the 'Wake on magic packet' and ' Wake on pattern match' functions in the Advanced tab and the Systems thread CPU usage went from 30-50% down to 5%. PC is Dell Optiplex on Windows 7 Enterprise 64bit, Core i3 2120, 4GB RAM.

Thanks again guys.

Levo said:

I have a Dell E6430S and I had the same issue, ~40% CPU hogged and the fan on all the time.
What helped me is Michaelmc's post, seems like we had the same issue.
I set the the two parameters he mentions to "Disable" and voile, fan stopped straight away

The path to use in case you are not familiar is:

Start -> Control Panel -> Device Manager -> Network Adapters
At this point, right click on the adapter you are currently using and choose properties
in the new window -> Advanced tab
and at the bottom of the left window you will see the two offending parameters

Thank you guys, I disabled these functions + some more functions in the same tab (in Network Adapter > Properties). I had this issue only after power up or wake from hibernation, every time going to sleep and wake from it solve the problem temporary.