ACPI.sys windows 7 process using 25-50 % cpu dell n5110 17R

Hi anuskadar,

I will recommend you to run the diagnostics on your system to check the hardware functionality:

• Restart your system and keep tapping "F12" as soon as the Dell logo appears.
• Highlight "Diagnostics" using up and down arrow keys and press enter.
• Diagnostics should start.
• The color bars will be displayed.
• Press "Y" to continue the test.

Please let me know if you get any error code along with the error message.

I will also suggest you to clean the air vents:

1. Check the vents on the computer to see if they are covered with dust and not allowing heat and air to pass through.
2. Turn off the System.
3. Unplug the AC Adapter.
4. Remove the Battery.
5. Use Compressed Air to blow the dust out of the vents.

Note: Do not use your mouth to blow the Dust out of a Laptop. If using a can of compressed air use the can according to the directions on the side of the can as you can cause damage to the computer if used incorrectly.

Keep me posted. Please reply for any further questions.

thanks for your quick reply. I have already run diagnosis test found one error in hard-drive (but it seems not a big issue) except it all others are working fine. I have done other your suggestions as well but still problem exist.do you have any idea about ACPI.sys and is there any relation between it and new LCD i have replaced.

hi DELL-Vikram,

thanks for your reply.i have format my hard disk and reinstall windows 7 again.then after i ran the diagnostics and no error i have found.all the test were success.but the problem still exist.

Hi anuskadar,

I appreciate your efforts. I will recommend you to run the symptom test on the system for slow performance:

1. Click on the link: http://dell.to/UhBp46
2. On "Choose a Diagnostics Type" windows, select 'Symptom'.
3. Select 'Slow performance, lockups and freeze' and click on 'Run Diagnostics'.

Also, run the 'Hard drive Stress' test:

1. Click on the link: http://dell.to/UhBp46
2. On "Choose a Diagnostics Type" windows, select 'Component'.
3. Select 'Hard drive Stress' and click on 'Run Diagnostics'.

Please share the results of both the tests.

If the above diagnostics pass, there is a possibility that one of the components got loose inside the system while replacing the LCD. You can try reseating the memory of your system (since this is the only component which is easy to reseat).

Note: Ensure that the work surface is level and protected to prevent either the surface or the computer from being scratched. Make sure the system is powered off by either shutting down the system through the operating system or by manually holding the power button. Ensure that all attached devices are powered off. Disconnect all external cables from the computer. Remove the ac adapter, battery. Also remove the Base Door.

To remove the Base Door:

Loosen the screw securing the access panel.

Lift up the access panel at an angle and remove it from the system.

Complete.

Once the Base Door is removed, use your fingertips to carefully push the retention brackets away from the top memory module until it pops up.

Slide the memory module out of the slot.

Complete.

The below video shows how to disassemble the memory.

http://en.community.dell.com/cfs-file.ashx/__key/communityserver-discussions-components-files/3524/2311.DR07_5F00_Memory_5F00_D.wmv

Note: While putting the memory back, make sure you hear the 'click' noise from both the latches.

If you still continue to face the same issue, try connecting a known good hard drive to your system.
Note: The hard drive on your system is a 'Field Replaceable Unit'.

You can also refer to the service manaul of your system to replace the hard drive: http://dell.to/Os22qq 

Keep me posted. Please reply for any further questions.