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Dell Defect Turning 2.2GHz CPU Into 100MHz CPU? 314

jtavares2 writes "In what is being dubbed Throttlegate, scores of users on many message boards have been complaining about nexplicably aggressive throttling policies on their Dell Latitude E6500 and E6400 laptops which cause their CPUs to be throttled to less than 5% of their theoretical maximums even while at room temperatures. In many cases, the issue can be triggered just by playing a video or performing some other trivial, but CPU intensive, task. After being banned [PDF] from the Dell Forums for revealing 'non-public information,' one user went so far as to write and publish a 59-page report [PDF] explaining and diagnosing the throttling problem in incredible detail. Dell seems to be silent on the issue, but many users are hoping for a formal recall."
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Dell Defect Turning 2.2GHz CPU Into 100MHz CPU?

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  • PDF Mirror (Score:5, Informative)

    by MBCook ( 132727 ) <> on Monday November 30, 2009 @05:11PM (#30274784) Homepage

    Here is a mirror of the PDF: mirror []. It was put up by the guy who discovered this, I'm just copying the link.

    User/password is "guest" and "guest".

    Be warned, it's about 25MB.

  • Bad Summary? (Score:3, Informative)

    by clang_jangle ( 975789 ) on Monday November 30, 2009 @05:15PM (#30274832) Journal

    scours of users

    That would be "scores of users", assuming submitter meant to indicate a number equaling or greater than a multiple of twenty. Of course it's hard to say really, as the link provided (the "many message boards" link which links to a single message board) doesn't say anything remotely resembling the claims of the submitter -- it's people complaining about "freeze/lockup".

  • by Anonymous Coward on Monday November 30, 2009 @05:20PM (#30274886)

    I started reading it before it got /.ed. He was able influence the time it took to do a Dell Diagnostic with heat management, that is running it several times in a row monitoring exhaust temperature. As it heats up > 60F it cripples.

    As a jab, my MacBook runs at 160F no problems :D

  • by 1080bogus ( 1015303 ) on Monday November 30, 2009 @05:25PM (#30274956)
    I called their Pro Tech support to help diagnose a very similar issue. The CPU's were running at 6-700Mhz. I spent 45 min on the phone with them until I finally found a forum explaining it had to do with the Intel SpeedStep feature. When you go into the BIOS, go to Performance, SpeedStep, and disable it. They said thanks, added to their Knowledge Base and gave us one more reason to get away from them.
  • by yknott ( 463514 ) on Monday November 30, 2009 @05:29PM (#30275002) Homepage Journal

    Here's a post on Dell's forums describing the issue []

    From the link:

    Some key points from the report (keep in mind this is specifically for the E6500 with the NVIDIA graphics option, but much of this likely applies to the E6400 and/or the Intel integrated graphics option):

    1. The problem is NOT an overheating problem - the system simply does not overheat. It is due to premature and overly aggressive attempts at thermal control, invoked at what are NORMAL processor operating temperatures (65-80 Celsius), possibly due to faulty ACPI "passive cooling" parameter definitions and/or control methods.
    2. The problem is substantially more pronounced when the system is docked.
    3. The problem is aggravated somewhat by the use of dual monitors when docked as opposed to a single monitor.
    4. Since the problem is all about temperature, the higher the surrounding ambient temperature in the room, the sooner and the greater the performance loss.
    5. The symptoms are much more highly correlated to elevated NVIDIA GPU temperature than elevated CPU core temperatures.

    Some miscellaneous corollaries:

    1. Any blockage of air inlets or outlets (including, of course, dust) will aggravate the problem.
    2. The reason people report shockingly high percent CPU utilization statistics when their system slows down is that the overall capacity of their processor is degraded by the throttling mechanisms. The same processes running on a CPU that is subsequently throttled necessarily will demand a higher percentage of the processor's remaining capacity.
    3. The reason some folks report persistent slowness even after installing software to prevent CPU downclocking is that more than one throttling mechanism is in play here. In particular, Software-controlled Clock Modulation (also called On-Demand Clock Modulation) occurs in an almost completely invisible manner, as opposed to performance state changes (which are usually monitored by common utilities). Another often-invisible throttling mechanism is Dynamic FSB Frequency Switching (where the FSB frequency is slashed in half), though if you prevent performance state changes, that takes care of preventing this too (since it's part of state P3).
    4. The reason there aren't more complaints (though many are accumulating these days) is that users who experience this problem simply have no way of knowing what the cause is and are likely to blame the wrong thing (Windows, recently installed software, cooling hardware, etc.). Untold masses may be adversely affected by this problem, but nearly all of them wouldn't know it because there's no way for them to tell. Also, the problem is at its worst only when in a docked configuration, which may not be common.
    5. The reason complaints are escalating now more than before is that this is the first summer that people have had this system (in the Northern Hemisphere, anyway). I think it's safe to say that ambient temperatures are higher for most E6400/E6500 users now.
    6. The problem can be substantially mitigated by pointing an external fan at the system.
    7. The problem can also be mitigated by software, such as RMClock, that can override the throttling mechanisms in question, at the expense of negating all passive thermal management (though critical temperature shutdown mechanisms may remain in place).

  • by Anonymous Coward on Monday November 30, 2009 @05:39PM (#30275150)

    Yes, can we scour the editors?

    More like scourge the editors

  • by D Ninja ( 825055 ) on Monday November 30, 2009 @06:11PM (#30275674)

    For those wondering what this is about - Turbo Button [].

  • by Fulg ( 138866 ) on Monday November 30, 2009 @06:19PM (#30275814) Homepage

    When you go into the BIOS, go to Performance, SpeedStep, and disable it.

    My brother's E6400 fixes the speed at 1GHz when SpeedStep is disabled in the BIOS (i.e. NOT at 100% - CPU is rated for 2.0GHz), so that's not always a solution. Is the thermal design so bad that they can't actually keep the CPU at full speed all the time?

  • by torklugnutz ( 212328 ) on Monday November 30, 2009 @06:28PM (#30275990) Homepage

    People get too excited about product recalls. It just means the manufacturer has to eliminate or at least mitigate the failure. In this case, Dell will issue Firmware A.02 or whatever and the problem will vanish. Not a big deal.

    I've had a lot of product recalls in my life because I drive a car and I have a baby. Apart from a few rare instances from Kodak and Honda, this doesn't mean the consumer gets a full refund and all of the products wind up in a landfill.

  • Mirror (Score:2, Informative)

    by xur17 ( 835191 ) on Monday November 30, 2009 @06:31PM (#30276052) Homepage
    Here's a mirror of the files. I only have the first file so far, but I will add the other one once it works: []
  • by Anonymous Coward on Monday November 30, 2009 @06:44PM (#30276272)

    Dell has aggressive CPU throttling in the BIOS. I have an Inspiron 6400 w/ Core 2 Duo 1.83ghz. In XP, Vista, and 7, it would throttle way the heck down and not turn the fan all the way up. Because the fan was annoying. It would go down to around 200mhz.

    I fixed it in software by installing RMClock and i8kspeedfan. But my computer was usually around 55 and went up to 65 playing HD video, and the fan would kick in, and suddenly it's really loud.

    Also helped to get one of those cooling pads with a fan in it.

    So I took apart my laptop. There were 1" thick sheets of dust between the processor and graphics coolers and then between them and the output duct.

    Cleaning them out, put it back together, now at full speed it rarely goes over 55. The BIOS throttling that kicks in at 70C or 75C or so hasn't come on since the software fix. Don't even need the Targus cool-pad anymore.

    So basically, Dell builds a system with inadequate cooling, that is disabled from maximum speed even when system policy is set that way, and instead throttles you down in the BIOS 'til you can't even move the mouse until it cools down. No option to allow the fan to go to full-speed, no way to do it except 3rd-party software, and really darned loud when it happens.

    It must've sucked to have a 2.3GHz in this thing...

  • by Zaphod-AVA ( 471116 ) on Monday November 30, 2009 @06:53PM (#30276442)

    Business systems.

    Systems intended for business use generally come with a 3 year warranty, which increases the quality of the system. If they know it will be their responsibility to fix it if it goes bing in 2.5 years, they must make a more robust system. You will have to pay a little more, but it's worth it.

  • by atomic-penguin ( 100835 ) <wolfe21&marshall,edu> on Monday November 30, 2009 @07:19PM (#30276810) Homepage Journal

    I have the same setup e6400 with an Nvidia Quadro NVS 160M running Ubuntu.

    Here is how I detected the problem. Add a CPU frequency governor applet to one of your taskbars. If you choose the "performance" governor profile with the applet, and your CPU scales down to 800Mhz on occasion, then you are experiencing this problem. You can also use the gkrellm application to monitor CPU, mobo ambient, and GPU temperatures.

    I've been monitoring the ambient temperature in my cube at work, and the temperature never goes more than a few degrees over room temperature. However the system begins running too hot, and scales down, for no obvious reason at all. A cooling pad or laptop stand, has mitigated the problem for the most part.

    The problem is very noticeable when a laptop with 4 Gb of RAM, and dual ~2.5Ghz CPUs, suddenly starts acting like it is running on a 486.

  • MIRROR (Score:5, Informative)

    by Anonymous Coward on Monday November 30, 2009 @08:03PM (#30277376)

    I click on the link and well, I think it's being hosted by one of these Dells

    At the end of one of the forums, someone links to a mirror. You can find the report here: []

  • by innocent_white_lamb ( 151825 ) on Monday November 30, 2009 @08:27PM (#30277616)

    I added a giant blob of silver paste
    Too much thermal paste is a Bad Idea. In fact, it's counter-productive.
    Use a very thin layer. There is about twenty times too much thermal paste in the little tubes that come with heatsinks and CPU's, and people who use all of it are defeating the purpose.

  • No sympathy from me (Score:3, Informative)

    by Rysc ( 136391 ) * <> on Monday November 30, 2009 @08:40PM (#30277728) Homepage Journal

    Don't fucking buy Dell. I thought everyone knew that.

    In before corporate purchase. Fire the guy who OK'd it!

  • by ickpoo ( 454860 ) on Monday November 30, 2009 @09:27PM (#30278110)

    I have this exact same issue on a Dell D620 Latitude. It typically happens when compiling code. The exact same symptoms - machine is working hard, begins to heat up, machine gets really slow and cools off but remains glacial slow. I've ran one of the speed / temp sensor plotting tools and can see the result CPU running at half speed but working at 100%. System is so slow that moving the mouse and the like around is practically impossible, only a hard reboot clears the machine, if I soft reboot the problem is even in the bios (pushing down arrow is about 1 second to move to next selection). The machine normally does ~6000 bogomips, when running slow is about 200 bogomips.

    I have had the motherboard and cpu replaced multiple times (4? 5? something like that). It always reoccurs a couple of months after the repair. This issue isn't confined to my D620, but all my co-workers which receive the same model Dell laptop have also had significant issues. It is so bad that we will be replacing our machines a year before they would normally be replaced. I'm lobbying hard to get something other than a Dell, but this is a challenge as they are my companies primary supplier.

    The most annoying thing, is when the problem happens and you call Dell up they are always - please reinstall the operating system. I know it isn't the operating system, I can reproduce it in the bios. But they still persist in believing it is the OS (and yes, they are trying to blame Microsoft, this case, purely Dell's problem).

  • by monkeySauce ( 562927 ) on Monday November 30, 2009 @09:38PM (#30278190) Journal

    I use to own a Dell Inspiron 5150 that had to have a motherboard replaced out of warranty. (I've since given it to my wife as she is a lighter user and it'll probably last longer with her). The most likely cause is a known but never acknowledged issue where with normal use the case wears against a component on the motherboard severing it. It's not the first such issue I've heard of.

    I too have an Inspiron 5150, and I too had the motherboard replaced past the original warranty; however it was still free as a result of a class action lawsuit over this problem in the 5150. []

  • Re:PDF Mirror (Score:3, Informative)

    by mariushm ( 1022195 ) on Monday November 30, 2009 @09:58PM (#30278320)

    Here's an "optimized for web version []" (5 MB, pics resampled to 150 dpi) and the original [] version.

  • Re:MIRROR (Score:2, Informative)

    by fgrieu ( 596228 ) on Tuesday December 01, 2009 @02:13AM (#30279934)

    This one seems to work []

Man is an animal that makes bargains: no other animal does this-- no dog exchanges bones with another. -- Adam Smith