Dell Latitude D830 getting to hot and throttling CPU clock

Question

Hi,

I have a Dell Latitude D830 with an Intel Core 2 Duo 2.4 GHz, 4 GB RAM and a Nvidia NVS 140M graphics card. I use Windows 7 with the latest graphics drivers from NVidia and the standard drivers from Windows 7 for the rest of the hardware. For measuring the CPU clock I use the program CPU-Z.

When I work with programs that are demanding off CPU power, like running a Backup that uses ZIP compressing or Adobe Lightroom and Photoshop, then first my fan starts running as hard as it can after a few minutes of work and then after another few minutes I can see the CPU clock going down. If I continue work for a couple of minutes the CPU clock goes down to 300 MHz from the actual 2.4 GHz it should have. I have SpeedStep enabled in the BIOS but set the minimum and maximum set at 100 % for both battery and plugged-in in the power settings of Windows. I can verify that these settings work because the CPU clock stays around 2.4 GHz if there is no load.

From this behaviour I assume that the CPU gets to hot under load and the emergency thermal throtteling kicks in. Can anyone confirm this? Is this normal? I hope it is not, because it prevents me from working normally with my notebook. At 300 MHz normal work with the aforementioned programs, especially Adobe Lightroom and Photoshop is not possible at all. I have to take breaks every few minutes to let the CPU cool down and go back to 2.4 GHz.

I bought it in early 2008 with three years extended warranty, so I still could call the Dell service about this issue. But I wanted to ask here what you guys think about the issue first.

Thanks and kind regards, Robert

Adrian Cox · Accepted Answer

I've found the cause of my problems: it took about 15 minutes to get in, but removing this dropped about 20C off the CPU temperature while Visual Studio rebuilds my project.

Adrian Cox · Answer

I'm having a very similar problem running Ubuntu on mine (D830, 2.5GHz, 4GB RAM, NVS140M). Sometimes the higher CPU clock values become unavailable for several minutes. It seems to be associated with high temperatures, but lingers a long time after the temperature falls. I had originally put it down to a Linux problem, and was considering switching to Windows 7 to fix it. I'm not so sure about that now.

carrson4 · Answer

Just FYI, in case you are interested.

I have the same Latitude D830 but with Vista that I've owned since 2007. I have been having performance problems lately. Ran a diagostic on the CPU fan and found that it is bad. I am getting it replaced and expecting that to fix my problems.

You may confirm that your fan is OK, but it sounds like it is. But I think I was having the same issue with the CPU clock speed getting reduced. I didn't confirm this and may try now just to see what I can learn.

Good luck.

carrson4 · Answer

Wow. That's dirty.

Does it void any warranty to get to this? I am still under warranty, and have a technician coming tomorrow to replace my fan.

Also, I am trying to find some software that would let me check my CPU temperature and/or clock speed, like the original post mentioned. Do you have a suggestion?

Adrian Cox · Answer

I'm not sure about the warranty. This area is under the fan, and the technician should remove any dirt before fitting the new one.

As for checking the temperature, under Windows I normally use Speedfan: http://www.almico.com/speedfan.php

carrson4 · Answer

Thanks.  My CPU is definitely getting too hot.  And I noticed that in the original post, they mentioned CPU-Z software.  I downloaded it and working on figuring it out.

the-ninth · Answer

Hi,

I am also still under warranty, so I'll get the technician to check first before I start to do anything myself.

For the programs, I used CPU-Z. In the default tab "CPU" it shows the Core Speed, which is the actual speed that the CPU is running at the moment. If you have Intel SpeedStep enabled (which it is by default with the D830) than you will see the Core speed being reduced when the computer is idle. This is normal and helps saving power. However, if you see the Core Speed being less than noted at the Specification field while the computer is under high load, then it might be thermal throtteling and indicate a problem with the cooling.

For artificially generating load to test this I use a program called CPU Killer. You can have it generate a certain constant load like for example 80 % and then see with CPU-Z over a period of 20 minutes or see whether the Core Speed is going down.

Both programs are free:

CPU-Z: http://www.cpuid.com/cpuz.php

CPU Killer: http://www.cpukiller.com

Cheers, Robert

PS: I had to edit photos from a recent photo session today. Since the D830 became unusable after 15 minutes or so I fetched a dry ice pack from the freezer and put it under the Notebook. Worked like a charm, the CPU stayed at 2.4 GHz for the remaining two hours of work. :-D

carrson4 · Answer

I just got my fan and heatsink replaced. Passed the fan diagnostic.

I downloaded CPU-Z yesterday and didn't realize that I was only running at 800 MHz instead of 2.0 GHz like I was supposed to. Now it shows around 2.0 like it should.

I tried CPU Killer, and even at 100% CPU for 15 minutes it never got below 1.9 GHz. Looks like I'm in pretty good shape now. I also noticed that the fan never kicked up to the high speed during the stress test.

I used a desktop fan and had my laptop sitting on it to make it useable until I got the internal fan replaced. I tried a bag of ice under and it didn't seem to work for me.

Good luck on yours. Maybe your fan is dirty? Does it pass diagnostics?

the-ninth · Answer

Hi,

I had the Dell service at my place today. They replaced the heatsink and the motherboard, the latter because I also hat a problem with the VGA out port.

The vent on the heatsink was really clogged with dust (it looked similar to the photo Adrian posted) so I guess that was the real problem and I guess cleaning would have helped even without replacing the heatsink. Good to remember for the time when the warranty expires.

I tested now 20 minutes of 80 % CPU load with CPU Killer and CPU-Z showed constant CPU clock around 2.4 GHz for all the time, so I guess the problem is solved.

Kind regards, Robert

hanspb79 · Answer

Hi,

I also found a small clog of equal size as poster in my laptop (a Dell D830 T7500 4GB). After 2.5 years with virtually NO cleaning, the laptop kept blowing at full fan speed even when the PC wasn't that occupied. Switched motherboard today and removed all cloggings.

Result:

- Temperature down 20-25 degrees celsius
- Sound much better (fans @ 50% rather than 100%)
- CPU working more efficiently

Thanks! The "new" PC is... well... like having a new PC. I will definitely do better PC-cleaning in the years to come!

Best Regards, Hans Petter

glnz · Answer

Everyone  - this thread is what I'm looking for, but how do I open my wife's D830 to clean out the dust?  Where are the instructions and maybe some pictures?  THANKS!!!

glnz · Answer

Bump.  Would really appreciate anyone's suggestion where to go to learn how to (a) open up our D830 laptop to clean it like Adrian's photo  above and (b) renew the heat sinks with that special chemical.  Thanks to all!

Adrian Cox · Answer

There's a step by step guide in the service manual <ADMIN NOTE: Broken link has been removed from this post by Dell>.

glnz · Answer

Mr. Cox:  Thanks.  Saw that and decided the info was way too skimpy for me to risk breaking the D830, so brought it to the local Dell auth repair shop and they did indeed clean out a ton of dust.  Question:  The D830 is now running good and silent - no fan noise and the bottom does not feel too hot.  HOWEVER, the sensors indicate a CPU temperature of 47 degrees Celsius - is that normal running temperature?  is it normal that the fans are NOT running at that temperature?  Thanks.

Adrian Cox · Answer

47 seems quite normal to me - the fans shouldn't start until it gets hotter.

Locked Topics – Laptops General

Dell Latitude D830 getting to hot and throttling CPU clock

Was this post helpful?