NOT AGAIN! My Latitude is overheating and the CPU is maxing out:

akwit: What you are describing is exactly what happens when clock modulation starts to throttle your CPU's performance down to a crawl. The Task Manager starts showing very high load percentages because the CPU is working like crazy to try and keep up due to the throttling. The mouse will lag and windows will open up very slowly.

Download ThrottleStop and monitor your computer with it. The two types of clock modulation should always be at 100% in the monitoring panel on the right hand side of ThrottleStop. If these ever drop down to less than 100% then that's what your problem is. Send me a ThrottleStopLog.txt file if you are not sure how to interpret the data that it collects.

If clock modulation throttling is a problem for you then put a check mark in the appropriate clock modulation box and set it to 100% and put a check mark in the Set Multiplier box and this will help prevent this throttling.

 

ThrottleStop isn't the solution to every problem like this, it's only a temporary fix, not a solution. Finding the software conflict (or starting over from scratch) is the solution.

 

Since Dell is not willing to take ownership of this problem and fix the clock modulation issues that can be found in a wide variety of their laptops, the only solution is to use a third party program like ThrottleStop.

What akwit has described is exactly what happens during a clock modulation incident. It has nothing to do with Windows or any software he is running on his computer and his CPU isn't overheating either. The Intel set thermal throttling point for these CPUs is 105C, not 70C. This problem can happen randomly and it may not be a problem for everyone's laptop but it is definitely a problem for some laptops.

If this is the problem with his computer and ThrottleStop can fix that problem, why do you consider that only a temporary fix and not a solution? For many users, it is a permanent solution. Waiting for Dell to do something about this on many laptops has proven to be a waste of time. The Latitude E6400 and XPS 1640 are at the top of the list for unresolved clock modulation problems.

ThrottleStop is a lot better solution than having to reboot your computer several times a day to reset the clock modulation register within the CPU.

 

Obviously, you know more about the inner workings of these things than me, but if the throttling point is 70C, that still shouldn't cause a problem. 70C is pretty hot for the CPU, especially in the E6400. The CPU in mine idles around 70F (accoring to HWMonitor) running regular office work in room temperature. After being turned on for 10 hours, it still remains below 85F.

If there are processes chewing up CPU time, then the temperature would rise, thus leading to measures such as increased fan activity or throttling to try to bring the temperature back down. Having users change the clock modulation themselves takes away a method that the system has to protect itself from heat damage, and the cause of the high temperature is still there. If dust is ruled out, then it has to be software. OEM images are extremely cluttered by things such as various GUI driver interfaces and such, which should be avoided whenever possible.

If Dell set the throttling point at 70C, there is probably a reason for it. While the CPU may be able to handle 105C, the system might not. There are also other components sharing the heatsink as well.

 

I went a couple rounds with Dell 2 yrs ago on this issue. Dell did not fix it or really have any idea why it was throttling. Installed Throttlestop and it fixed the problem. Other than the throttling issue this has been a great laptop.

Throttlestop got me past this issue and I have enjoyed the system since. Made a minor bump out of an insurmountable mountian.....give it a try and solve your issue.

 

Thanks for the vote of confidence jcthorne.

Clock modulation throttling was designed by Intel to control the processor temperature after it goes beyond the 105C throttling point and is heading for the 130C shutdown point. No manufacturer was supposed to be using this at a core temperature of only 70C. That's ridiculous.

Last time I checked HWMonitor, it's not using the correct TJMax value for many of the 45nm Core 2 CPUs. Have a look in the hwmonitorw.ini configuration file and make sure this is set correctly. For a T9400, it should be set like this.

CPU_0_TJMAX=105.0

Head to the Intel website and look up your CPU if you're not convinced.

Intel® Core?2 Duo Processor T9400 (6M Cache, 2.53 GHz, 1066 MHz FSB) with SPEC Code(s) SL3BX, SLB46, SLB4D, SLGE5, SLGEK

I don't think you understand the problem. When clock modulation throttling is being used to throttle the CPU internally, the Task Manager will start to show normal processes using up large percentages of the CPU. Once you get rid of the clock modulation throttling, all of these processes will immediately return to normal amounts of CPU usage without needing to reboot or do anything else. The computer will instantly return to being usable again.

With other laptop models there might be a lot of things that need to be checked first but with this laptop model, the first thing a person should check when they are having this issue is clock modulation throttling.

Using ThrottleStop to turn clock modulation off is not going to hurt the CPU. If the CPU ever gets hot, it can still use its own clock modulation feature just fine and will override any ThrottleStop settings to control the heat of the CPU from reaching the thermal shutdown temperature. There are two completely separate systems in Core 2 CPUs. One controlled by user settings and the other controlled by the CPU itself which takes precedence over any user settings.

Dell's use of this "feature" is a bug and has nothing to do with the safe running of this laptop. There are viruses out there that are not as brutal on performance as Dell's clock modulation throttling schemes.

 

This begs the question, why does Dell make it so?

GK

 

John-

How do you feel about throttle stop?

I have reinstalled windows multiple times on this unit and all of ther others I have as well. This throttling issue ALWAYS comes back to haunt me. Also, why have I never had this problem undocked? In two years now, not once has the system throttled while undocked.

Also, when I take the laptop out of the dock, the bottom is almost too hot to the touch. Can this have anything to do with whats going on?

The resting temp for me when docked is about 55 while undocked its around 35...

Have you uses this ThrottleStop program?

I dont believe it is the software.

My worry about using this ThrottleStop app is my limited knowledge of computers in general; will this be voiding my warranty and what are the chances that it could ultimately cause damage to my system?

btw-i removed the "Windows Sharing Device" under services and applications but like a virus, it keeps popping back up in my task manager and I want it gone completely. What am I doing wrong here?

 

What other devices do you have connected to your network? It's likely another system that has something improperly configured with Media Center or Media Player.

Interesting, that explains the really low temperatures. I am now idling around 115F.

But when you first got the system, this didn't happen?

 

No.

With every system i have had, this appears to happen over time-never out of the box. Its as if the system is deteriorates over time...

Since my frist Latitude, I have easily reinstalled XP and later 7, at least twice a piece. It has nothing to do with the OS.

Lastly, theres no coincidence that nearly every person i have spoken to who is using the docking station with two external monitors, is have throttling issues.