Compaq 6910p Runs slowly when plugged in

[anbello262]

Hi, everyone
I'm having a problem with an old laptop. Its a Compaq 6910p (T7300, 2gb of ram, windows 7 64bits). It works perfectly when I use it on battery, but as soon as I plug the charger in it gets really slow (REALLY slow) and Task manager says CPU usage goes up to 100% (only by having the power cord connected, no programs running). When the charger isn't connected, processor usage goes back to normal levels.


What could be going on here? Can anyone help me?

 

[jarotech]

Hi, you have to let us know which process is using the most percentage of the CPU. Go in the Task Manager and click on Processes, then on CPU, you will see the most demanding processes at the top. If they are not using enough, click on the lower left corner "Show processes from all users".

 

[anbello262]

Yes, I've already done that. While it's unplugged, it sits about 7% usage (common programs, like taskmgr and explorer).
As soon as I plug it in, withouth changing anything else, taskmgr starts to take about 50-70%, explorer the rest, and there are no other significant processes. It's just as if the CPU becomes really, really ineficcient as soon as it's conencted...
I checked Energy/battery options and set everything to work exactly the same when it's running on battery as it's on AC, and no change. I also tried setting everything to max performance when running on AC, and no luck. Later I'm gonna try to borrow a different charger, to see if that's the issue, but I still can't understand how a faulty charger could make the CPU work this way...

 

[jarotech]

What you can verify, connect the adapter without the battery. Also maybe you have a virus, check for that also.

 

[anbello262]

It's not a virus, as it's a completely fresh install of Windows 7 64bits. I tried connecting the adapter without the battery, and it still works terribly.

It was the AC adapter all along, i tried with a different one I borrowed and there was no problem. I'm gonna buy a new one as son as I can. Thanks for your help.


Can anyone explain how a defective adapter could cause this kind of problem? It maybe caused some kind of power throttling, as it was unable to provide the power needed?