Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

A problem that has flabbergasted me now for a while. On a Dell Latitude E6410, everything works swimmingly when the computer runs on battery. the moment that one inserts a powerpack (e.g. connects the laptop to the electricity net), two things happen (unclear if correlated):

  • After between 10-40 minutes - the computer will become very slow and unresponsive. Initial checks don't indicate that this has to do with back-up software (e.g. dropbox or Mozypro) or virus scanner, but cannot fully rule out. This is the main problem.

  • Also - the moment that the power pack is inserted - eitehr Intel Rapid Storage Technology will "detect port 1", or if the former is disabled, Windows will suddenly detect a non-existing D: Drive / DVD drive. (which makes me wonder whehter it misreads the battery pack as an external storage location???). As said - not quite clear to me whether correlated with the problem per above, and if so, what the causal mechanism is, why the computer slows down...

Anyhow - this completely confuses me - and would love to hear any thoughts on the cause, furhter diagnosis and/or and ideally resolution of this problem...

Many thanks in advance,


share|improve this question
You could mess with your windows power options, while your waiting for an answer. If you create a new power plan you can customise it without messing with the standard plans. Then change the advanced settings. In win7 power options are much more extensive than before. – Psycogeek Jul 29 '13 at 19:02
Use the resource monitor in win7, very valuable tool. C:\Windows\System32\resmon.exe with it you should be able to determine what is using cpu, what is working the disk, and even what net stuff might be going on. – Psycogeek Jul 29 '13 at 23:24
Thansk for ur comments. i have been using resource monitor and illustro. the weird thing is that random applications (teatimer.exe, launchy, explorer) suddenly become cpu hogs and spike up - if i close one than the other ones take over the CPU hog role. So resource monitor doesnt seem to show the "underlying cause" why there is a CPU constraint... let me know your thoughts! – Wouter Jul 30 '13 at 17:14
It is my understanding that if the cpu steps down, the visable indicators of 100% usage are working in that smaller area. So i would want to see my stepping using CPUZ or rightmarks or anything that would show either the cpu Clock at the moment (some cpu monitors) or the stepping live. I do not know how (overheat) throttling displays. Then some way to test your CPU and speed in a controlled way. using prime or intelburn or something. So you can be there and SEE live. I could suspect a baddie or a bad dll too (AVcheck) also a low possibility that a hard drvie is not reacting Disk Speed test – Psycogeek Jul 31 '13 at 1:16
Superhelpful. Please forgive my ignorance: • I didn’t manage to install RMclock – but installed CPUID. Which metrics should I be looking at? CPU clock numbers (Core Speed, Multiplier, Bus speed, QPI link)? – although they didn’t seem to change much at slowdown. Should I look at other indices / metrics? • When you mention AVcheck - do you mean there is maybe process AVcheck.dll that I should check if it is running on my comp, or is this a program that I should download? • Disk speed test – do you recommend downloading a specific one? Many thanks in advance, very helpful, W – Wouter Jul 31 '13 at 15:53

This is usually caused by the 'Connected' power scheme having too many power restrictions on it:

Follow the steps and make certain that your connected or plugged in power scheme isn't using greater energy savings settings than your battery power scheme.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.