Hi ! My Lenovo A55 desktop PC cannot be powered off properly, it always comes back on right after the power down sequence. Tried various setting in the setup but they seem to make no difference. I need to switch the PC off at night and would like to start it via LAN from a remote PC. Looking forward to hear from you!

okay if your PSU is working than have you checked the other hardware? for example check your MEMORY RAM sticks and check if they are properly in if they are out the pc will not start. also!
if the power supply is good than your motherboard should have an LED on it somewere look for it and power it on .. if this LED doesnt turn on than it means it gave out and you need to replace it .. cause of this? maybe a power surge or static or the light went out and came back and it fried it. i hope this helps

There are two possibilities: one is the factory installed a single core CPU and thus set the BIOS to correspond to this, and two is that you might be able to update the BIOS using BIOS update from Lenovo; make sure that the update states that it will take care of the single to dual-core cpu discrepancy. Please be aware that updating BIOS can be a very tricky procedure. If correctly done, everything works fine; if not, you can easily have a non-working motherboard.

Bad Power Supply, Replace it.

Right click on 'my computer' > manage > device manager > at the right side of the list search for 'Sound, Video and game controls, right click above it, and select properties and click 'Roll back' ( also update the audio driver)

try this link, see if you can find the sound driver for Windows 7 , IBM site

http://www-307.ibm.com/pc/support/site.wss/MIGR-66440.html

Have you installed the audio driver? If not you need to install the audio driver and any other devices that has not been installed.
The same model ThinkPad can have different types of network, video and audio drivers and unless you know exactly which one is installed in your ThinkPad, you need to download all the drivers and install each driver until you find the right driver.
When you download the drivers, write down the device driver and it’s file name so you have a record of which driver you are installing and which directory the unzipped files are located on your hard drive.
Go to the IBM/Lenovo WEB site - support/download page and download the latest Windows XP or Vista device drivers for your model computer, Use this link: -
http://www-307.ibm.com/pc/support/site.wss/product.do?template=%2Fproductselection%2Flandingpages%2FbrowseByProductLandingPage.vm&sitestyle=lenovo&brandind=10&validate=true
You can download the various drivers and then you click on and run the various driver files, they will then unzip and expand into a sub folder on C:\drivers Then install the various drivers from this folder (run the set-up file).

it should just be a power button, just like everything else, push to turn it on

your mocs cell waltage goes down.
CMOS cell gives power to bios flash memory when it goes to low bios forgot settings after power off.
So purchase new CMOS cell it is on motherbord change it then save settings then it not forgot settings even after power off.

Thanks for using fixya.

sounds like the mother board maybe on its way out - is it under warranty?

If u could not hear the audio means check wheather the audio drivers have been installed properly.....if not get the drivers from the site WWW.SOFTPEDIA.COM
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