Diagnosing CPU issues

Question

I have been struggling with spikes in CPU that cripple my Dell Latitude 6410 whenevere it is plugged into the powernet. I am failing to diagnose the issue - and would love your help:

• Have tried different powerpacks, powerplugs, batteries, to no avail

• CPUID shows that CPU is around 1200.23MHZ, bus speed at 133MHZ in both cores

• Installed Illustro, Resource Monitor, Process Explorer and CPU ID. There are no new processes that are started when the computer is plugged in, and the CPU capacity is taken up by a mixed range of regular processes (e.g. explorer.exe, taskmgr.exe, etc.) that suddenly start to take up 99% of capacity. Hence - the issue seems not to be that these processes suddenly become more hungry, but that the overall CPU capacity suddenly becomes less.

• I would like to emphasize that i have tried to kill any of the processes that start to hog CPU power, but to no avail. my strong suspicion remains that it the processes that resource monitor as starting to absorb the CPU capacity are not the root cause of the problem, especially as they are very standard processes, and the issues still occur when each of these processes killed (in which other cases other programs start to spike up). But i don't know how to diagnose which other program / issue might cause this

See copy of typical issue occurance per below (System Idle dropped to 1% pretty shortly after, CPU valuses in brackets)

• System Idle Process (18.55), procexp64.exe (15.66), Skype.exe (9.89), perfmon.exe (8.54), iexplore.exe (6.93), TeaTimer.exe (6.11), iexplore.exe (4.2), etc.

  • However - i am failing to find a diagnostic / measure that explains why this happens / what is the rootcause, and how this links into power plug-in. CPU ID shows that clock speed, bus speed, multipier of each core stays stable.

  • I am unfortunately not that technically advanced - so much much appreciated if someone can suggest other tests / diagnostics / metrics that i should look at to hopefully find a root cause.... Please let me know which program to install, and especially which metric to look at to compare situation when computer is plugged in vs. situation when computer is plugged out....

  • The power plan settings are System cooling policy (active plugged in, passive on battery), and maximum processor state at 100%.

Constant freezes is very frustrating, so many thanks in advance,

Wouter

Answer 1

Check your power settings. Windows has the option to "throttle" the CPU on a power plan in order to save power. This is designed usually for use while on battery power (to make the battery last longer), but it seems like somehow that was enabled on the "When Plugged In" part of your power plan.

1. Open the Power Options (Start > Control Panel > All Items > Power Options)
2. Find your currently active plan (it should be selected) and click Change Plan Settings
3. Click Change advanced power settings at the bottom
4. Find Processor power management > Maximum processor state > Plugged in and make sure it's set to 100%