CPU 100% on ac adaptor xps1330

Hi guys, I currently have a xps 1330 with
Intel core 2 duo T7500 2.2ghz
Nvidia 8400M gs
3GB ram
Operating on Vista home premium sp1

So far everything was going well on my laptop,
did the tweaks I found on the forum and the laptop was performing
very quickly. I noticed it was overheating however and called dell
and they sent me a replacement motherboard.
Everything was working fine at first until I notice a huge performance
drop. The computer took around 3-5 minutes to start up and all the programs
took quite a while to start. The cpu usage was constantly reaching 100%.
After calling dell a few times and running a bunch of test and spyware
removal tools, the problem still exist. I noticed today that this problem
is only occurring when the ac adapter is plugged in and will work fine
on just battery power. I called dell again today to report this finding
and they still couldn't figure out what was wrong, they were just sure
it couldn't be a hardware error. They can only suggest I do a clean install
of Vista.

Now I'm not sure if that would help, as I've tried reverting my laptop back
to factory day 1 settings and saw no improvement. I'm wondering if anyone
here may have any ideas as the cause of the problem before I do a clean
install. Again, this problem just arose after a motherboard replacement, though I don't know if that would have anything to do with it, but seems to me to be the cause.

Thanks for any help

-H

 

Check the power profile and the settings for each profile. Be sure to put your power profile on "High Performance." Click the battery icon on the bottom right, click more power options, click change plan settings under High Performance, then click change advanced power settings. Click Processor Power Management, and set minimum processor state and maximum processor state 100% plugged in.

 

I have been getting 100% cpu usage on startup for maybe 10 minutes overall, and making all my temps peak for everything. Everything reaches about 70, but settles down after 10 minutes to normal idle temps. I did not used to get 100% cpu on startup.

 

The cpu usage is still high and computer still lags even after editing the power options unfortunately.

 

what bios are you running? are you using all the latest drivers?

 

Bios is A12 and all the drivers are up to date

 

I've downloaded a program called notebook hardware control (NHC)
and found out that my cpu is currently being underclocked. When plugged in
its only going at 2.194 ghz and 2.195 unplugged. I tried to set the cpu at max performance and it comes up an error and won't let me. I think this may be the cause of the slower performance. Any ideas how to resolve this?

 

Go to task manager and see what process is actually using the processor. That will help determine what is at fault.

 

Check in services if you enabled Windows Search. If it is then disable it or set manual. Also check .Net Runtime Optimizer service if you have it. These two can be very taxing if they are running.

Go to start-->Run and type msconfig. Go to startup tab in msconfig and uncheck anything that you do not need. Personally I clear everything other that the touchpad app. Unless it is really critical for the system to operate anything that start can bel disabled and started manually if needed.

If you have superfetch enabled you can try cleaning the windows\prefetch folder pf files. I am not sure for Mobo replacement but after Sp1 upgrade I had to do this to get my performance back again.

 

Did u check if the charger maybe it is causing the problem? Coz it happened to me before.. the system told me that the battery is not charging and performance is gonna be low or sumthing like that.....had to get a new charger but at begining was ok.... but then again i didn't have a mobo change..

 

Well in task manager, it showed that task manager and a couple other system processes were causing the 100% load. I've done a clean install of vista today and updated the drivers once more. The performance was back to normal for the most part it seems until I plug in the adapter. I restart windows and get the adapter couldn't be identified and so forth so I looked through the forums and found out how to resolve that. However the performance still drops when plugged in. Using rmclock, it reports my clock speed at 1.2-2.2ghz on batter, and only .8ghz when plugged in.
Any ideas?

 

Hi

I had the same problem as you on HP Compaq 6710s (dual boot xp+suse). I've tried everything to no results. In my case, the problem was caused by the torn cable from the AC Adaptor. After I straight it up a bit, the problem was gone. So it's not a OS problem since the CPU went to 100% both in XP and Suse. Hope it helps.

 

I have the exact problem on my XPS M1330. Did you ever find a solution?

 

Well I ended up returning the laptop since a few more issues came up, but I did find a solution. After doing a clean install the cpu usage wasn't as high anymore, but i still got the performance drop with the battery issue. After trying to convince dell that I did all the troubleshooting steps, they finally decided to replace the motherboard again and after that, everything was perfect again...well for the most part.
So basically, it appears there may have been a short or defect in the
motherboard somehow, since that caused/solved the problem.