Posts Tagged ‘overheating’

Too Good to Be True? My MacBook Pro: First Cool, Now Quiet

Friday, May 15th, 2009

This will be a brief coda to a couple of recent posts in which I related how I finally solved an ever-worsening (OS changes?) problem of overheating on my first generation MacBook Pro. See “What a Relief! MacBook Pro Overheating Problem Cured—Really” and “Can’t Boil Water With Vista on My MacBook Pro Anymore” for the details. The solution turned out to be undervolting—setting cpu operating voltages at values (determined by experiment) below the overly conservative ones set at the factory. A great little piece of software called CoolBook enables one to do that on the Mac. A similar program (RMclock) is available for Windows.

I can report that I have encountered neither high temperatures nor computer instability since adjusting voltages lower with CoolBook. After a couple of weeks of stress-free lower temperatures, I realized that the previously necessary evil of the constant droning of the MacBook Pro’s cooling fans was no longer necessary. In my earlier efforts to control temperature I had installed a System Preferences utility called Fan Control. This allowed me to set the minimum temperature at which the fan speed would start ramping up and the rate at which it would increase with temperature. This was not a solution for sustained operation at the highest default voltage used when the cpu was running at maximum speed, but I think it did keep things cooler than what Apple’s normal fan speed algorithm did.

It may seem funny that Apple would have such high operating voltages coupled with such puny fan cooling; but I think we have reason to believe that Steve Jobs hates fan noise (I’m with you there, Steve), perhaps beyond reason. I remember buying a third-party fan that sat on top of my first Mac, the mighty one-megabyte-RAM Macintosh Plus. Word was that it was needed to prevent premature death of the convectively cooled Mac. I can imagine Steve telling the engineers to get rid of that fan noise on the MacBook Pro, or else.

The fans on my machine, even though one of them was relatively new, having been replaced under AppleCare when my original hard drive croaked (Fatal But Survivable: A Hard Drive Transplant Story), seemed to have gotten noisier over time, from overuse I suppose, so they were annoying me more. Why not get rid of Fan Control? Removing it from the System Preferences Panel wasn’t hard (Ctrl-click and make selection), but this merely put the fan speed versus temperature profile out of my control, while leaving the last one set by Fan Control in effect. I saw one unfortunate on MacUpdate warning people not to install Fan Control because it permanently changes the fan settings. This is fortunately not true, but the folks that make Fan Control should probably do a better job of letting people know how to completely uninstall it. Here is the rest of the procedure: remove the following files and folders (both on your start disk)— /Library/StartupItems/FanControlDaemon and /Library/PreferencePanes/Fan Control.prefPane.

In order to have a way of monitoring temperature and fan speed I went back to running smcFanControl, a program that only allows one to set the minimum fan speed. I used it to set the minimum speed back to 1000 rpm, down from the Fan Control minimum of 1600 rpm I’d been enduring. This is really quiet!

Having smcControl running enables me to step in to raise the fan speed if necessary. Shades of the past: yesterday I was reinstalling the iPhone SDK as part of a long battle (probably not to be related here) to be able to test my in-development iPhone app on an iPod Touch, when I noticed the smcFanControl temperature reading said 90° C, while the fans were still whirring away at less than 2000 rpm. I used smcFanControl to raise the minimum speed much higher manually, which had the desired result. When that taxing installation procedure was over, I set the fan speed back to 1000 rpm.

Now that I finally have what I thought I was getting when I bought the MacBook Pro, this should be the last I’ll have to say on the subject of temperature control and fan noise. Peace.

What a Relief! MacBook Pro Overheating Problem Cured—Really.

Friday, April 17th, 2009

Just in case anyone has arrived here desperate for a solution to MacBook overheating, let me put it in this first sentence: CoolBook is what you need. I last wrote about the ever-worsening tendency of my first-generation MacBook Pro to go into a runaway heating mode back on November 22 of last year in an optimistically titled post called New Firefox Cures Overheating? I knew better than to be confident that something as simple as a browser upgrade could have taken care of my overheating problems, but I wanted so much to believe it. The Firefox upgrade probably did alleviate overheating associated with Firefox, but before long it became obvious that it was only a small part of the problem.

Since my lonely corner of the blogosphere receives several visits daily from unfortunates with the same overheating problems (I can tell from the logs of their visits: Google search terms), I’ve felt bad that all I was really offering them was the knowledge that they were not alone, even if Apple has never said anything about the problem. My computer got a slight amount of symptomatic relief by using the Fan Control utility, which goes into the System Preferences panel. With Fan Control, I was able to control the fan speed versus temperature profile to some degree, but the maximum fan speed, no matter what temperature it kicks in at, is no match for a true runaway heating episode.

The overheating problem only got worse for me with the 10.5.6 OS upgrade. Some apps became completely unusable. For example, Winclone, a great program for backing up your Boot Camp Windows partition to a compressed file on your Mac partition, thus allowing you to have a Windows backup on your Time Machine drive, would reach 100° C before 5% of the Windows partition had been read! The temperature never reached a plateau, and the high temperature caused a shutdown the one time I decided to let it keep going and hope for the best. I tried reverting back to an earlier version of Winclone, which had never caused a problem before, but that didn’t help.

The funny thing was that the runaway heating often seemed to be associated with periods where one might expect the computer to be cooly twiddling its thumbs. For example, EPSON Scan, the software that runs my excellent Epson Perfection 2450 Photo Scanner, would operate at a reasonable temperature when actually scanning, but once I clicked to tell it that, yes, I wanted it to scan another page, it seemed to go into a rage for some reason, and I heard, not the purr of a resting Mac, but the ever loudening buzz of the cooling fans, which were vainly trying to get it to cool down. Click to begin the next scan, and the temperature would drop. Similar odd behavior was observed with the Microsoft Office upgrade installer. Once the installation, which occurred coolly enough, had finished, the fans would start to buzz; and quitting the installer was the only way to bring the temperature back down.

There were also certain websites that would cause both Safari and Firefox to get a fever that ramped up rapidly and could only be stopped by jumping to another site. This could happen on certain sites without any video or anything I’d seen associated with the problem before. A web site featuring high school athletic event schedules was one such innocuous looking site with pyromaniacal pages.

At some point a few weeks ago Safari became completely useless, as it would invariably start up the runaway heating ramp within seconds after launch. How can it happen that a program permanently changes its behavior? I don’t know, but reinstalling with a freshly downloaded copy of Safari 3.2 did not help. Ordinarily I wouldn’t have tried the Safari 4 beta, but I had nothing to lose at that point, so I installed it, and it ran normally. I believe running Safari 4 instead of its formerly stable predecessor actually caused an overall lowering of the average temperature at which my MacBook Pro ran, but it by no means cured the overheating problem. I was pretty well resigned to having it indefinitely until the day before yesterday, when I got my hopes up again.

I can’t remember how I came across CoolBook, but I downloaded and installed it yesterday, and it has really solved my problem. Hopefully it has no undiscovered side effects. How does CoolBook work? In a word: undervolting. CoolBookController (to use the program’s full name) allows you to scale down the operating voltages assigned to different frequencies, thus allowing the computer to run at a cooler temperature without reducing the computing power, which depends on the frequency. Apple has set a default table of these voltage and frequency pairs that is quite conservative. Chips vary, and Apple must have chosen the voltages so that almost no cpus will be unstable for any frequency. This makes life easier for Apple, from the warranty standpoint no doubt, but in the case of the laptops it sells, it makes for a lot of unnecessarily high operating temperatures. So why doesn’t Apple do a chip-by-chip calibration to minimize the number of hot MacBooks? Well, it probably took me at least two hours to get CoolBook all set up for my MacBook Pro. First, it takes a while to figure out what to do, though everything you really need can be found in the instructions.

Then it’s just a matter of trial and error to determine what is the lowest voltage you can use with a given frequency on your machine. A utility called CPUTest is provided to verify cpu stability for the voltage/frequency combination you choose. This utility evidently does uninterrupted heavy-duty computations until it catches an error or until you decide it’s run long enough to call it a successful combination. The documentation recommends running the test for at least ten minutes; so you can see how an hour can easily be used up. In my experience, failures usually occurred in the first minute or so though.

I followed the recommendation to determine the maximum frequency at which my machine could run without trouble at the lowest voltage setting of 0.95V. Following the result reported in the documentation I tried 1.837 GHz for this voltage and got an immediate black-screen shutdown. i should have known mine couldn’t match that. I cut the trial frequency way down and worked my way up. I found 1.503 GHz was the highest stable frequency. Apple’s default frequency for the lowest voltage is 1.0 GHz.

Here are the frequency/voltage pairs that my formerly hot MacBook Pro ended up with (original Apple voltage settings in parentheses):  1.503 GHz, 0.95 V (1.1125 V); 1.67 GHz, 0.9625 V (1.1625 V); 1.837 GHz, 1.0125 V (1.2125 V); 2.004 GHz, 1.0875 V (1.2625 V).

How much difference do the lower voltage settings make? A very big difference in operating temperature for my machine. It has cool (58° C) and silent operation during times of cpu-loafing such as the computer is experiencing while I type this piece. During the stress of the CPUTest, I saw the temperature reach 98° C for the 2.004 GHz frequency, but it stopped there, and I know from experience it would only have been stopped by a computer shutdown at 115° C using the Apple default voltage.

The fix of the overheating problem still doesn’t explain why the computer thinks it needs to go to to maximum frequency for no apparent reason. CoolBook’s cpu-frequency monitor allows you to see what the current frequency is. Sure enough, it goes to the maximum 2.004 GHz on that baseball schedule page. I think I may just now have seen the culprit though. That page has one of those continually scrolling stock-ticker-like message things, which perhaps eats up computer cycles somehow. If that’s it, it doesn’t even have to be visible to cause the effect.

I also see that gathering permissions info in Disk Utility throws it into the highest frequency mode, as I would have expected from previous temperature rise observations. Why is that, I wonder? Quitting Disk Utility in midstream had no immediate effect on the computing frequency though. It’s stuck there at the highest frequency, though no running program is doing anything I’m aware of. I think this must really be an OS X issue. Fortunately, instead of being in the upper nineties, the temperature is around 70° C. That’s still high enough to cause an annoying fan noise though. Already complaining!

Anyway, the $10 I spent on CoolBook was nothing for the amount of relief it has brought. I’d have spent ten times that much to be guaranteed a solution to the overheating problem, which was ongoing and had become quite limiting, witness my not being able to run Winclone. This time, there really has been a solution. I successfully made a backup with Winclone yesterday at around 70° C. Unless Apple breaks CoolBook with its next update (and the danger of that will give me pause), I’m set for being a normal Mac user for the foreseeable future. CoolBook is evidently the creation of Magnus Lundholm and is found on a web site with an se domain. Hats off to the guy in Sweden!

New Firefox Cures Overheating?

Saturday, November 22nd, 2008

In my last post, Boiling Temperature—Not Just for Vista Anymore, I recounted my experiences with my first generation (2 GHz Core Duo) MacBook Pro overheating to the point (121°C!) where it shut down automatically. Since I had never seen this behavior before, I speculated that it might be related to the latest version of Mac OS 10.5, though of course I feared it might be some newly developed hardware problem.

Such sudden shutdowns due to overheating, were they to continue, would not only be inconvenient but would seem likely to decrease the lifetime of the computer. Since I last wrote, I witnessed yet another runaway heating incident. The maximum revving of the cooling fans alerted me to the potential problem. A quick check of the CPU temperature showed it had already reached 116°C, so I quickly saved anything that needed it and shut the computer down. Upon restart it was back to normal operating temperature. I was facing the prospect of taking my MacBook Pro in for a checkup, thus losing the use of it for an indefinite period of time, without much confidence in a simple solution being found.

Since that time, I’ve become guardedly optimistic that the problem has been solved, as my machine has been doing a pretty good cucumber imitation for the past ten days or so. I believe that the fix was a routine upgrade of Firefox to version 3.0.4. It was only a few days after I had given Firefox the go-ahead to install the new version that I came across a topic called “Overheating caused by Firefox 3 and/or Flash?” in the Apple Support Discussion section devoted to “MacBook Pro (Original) > Internet, and Networking the MacBook Pro”. Some pretty strong circumstantial evidence was presented that the then current version of Firefox (as of October 31, 2008) could cause runaway temperature increases, even when it was seemingly just idly standing by.

Now, I routinely run both Safari and Firefox all the time. Firefox is necessary for editing this blog for example, as Safari destroys text formatting when it’s used to edit a post with WordPress, and I still encounter web sites (government usually, it seems) where Safari doesn’t work. Anyway, I’m in the habit of using both at the same time for general browsing as well. So it is safe to say that Firefox was running every time the runaway temperatures were encountered.

I don’t know what kind of software bug could cause overheating, but I’m hoping that there was one in Firefox that has been been fixed in the latest version. I have a gut feeling that my problem has been solved. Yeah, I know, it sounds too easy, but sometimes we get lucky.

Meanwhile, I’m taking it as one more sign of my own return to health that I’ve gotten a mild cold. I apologize to any regular readers for yet another computer post. I promise I’m working on something else.

Boiling Temperature—Not Just for Vista Anymore

Saturday, November 8th, 2008

As I slowly crawl my way out of a case of “walking pneumonia” that has lasted for over five weeks now, and while I’m still not up to anything that requires much energy, mental or physical, let me report on the health of my MacBook Pro system, which has been occasionally running a fever far, far higher than the low grade ones I’ve been experiencing from time to time. Beyond entertaining the (probably few) who enjoy accounts of unsolved computer problems, I’m hoping that, in case others have encountered similar unexplained behavior, this report might provide data to help someone figure out what the likely cause of the problem is.

Back in March in a post called Vista on My MacBook Pro is Hot—Boiling Hot!, I reported on the high temperatures (up to 100° C or 212° F, the boiling point of water) I’d observed while running graphics-intensive software under Windows Vista installed on a Boot Camp partition on my first generation MacBook Pro. Since not a day goes by without a few visitors arriving at this blog due to Google searches on terms such as “macbook pro runs hot in vista,” I’ve concluded that the high temperature under Vista must be something that has caused concern to a lot of people. I have no way of knowing if this is mainly Apple’s, Intel’s, or Microsoft’s fault, though I suspect it is Apple’s, since Vista’s operating temperature would naturally have a much lower priority for Apple.

I’ve recently observed temperatures under Mac OS 10.5.5 that make the Vista temperatures seem mild in comparison, however. The first new record-setting temperature occurred for no apparent reason several weeks ago. I had given Microsoft Office 2004 Update the go-ahead to install the latest update of Mac Office 2004 in the background while I went about my business. After a while I noticed that the fans were revving up higher and higher. I checked the temperature with the iStat Pro widget and saw that the MacBook Pro was hot all right, having reached 104° C with no sign of starting to cool. I realized that Microsoft Update was still open even though the update had been completed some time ago. Could that be the source of the heating?

Sure enough, when I quit the Update program, the system started to cool right away. It may have been a coincidence, but it was too dramatic not to convince me that somehow Microsoft Update had put the system into a a funny state that made it run hotter and hotter. Since this had never happened before, and since it seemed to be associated with the Update software, which had run numerous times before, I can only guess that the problem has to do with the Mac OS version I was running under, which at that time could have been as early as 10.5.4.

Perhaps running the Update software had disabled the fan response to temperature rise and then, upon completion of the update, the fans had kicked in and would have brought the temperature down anyway. In that case the temperature drop when I quit the Update program would have been a coincidence. The fans were definitely running at high speed by the time I quit Office 2004 Update, but not having checked the temperature earlier, I can’t say that it hadn’t actually been higher than the 104° C I observed just before I quit the Update. It’s hard to get rid of that gut feeling that the Update software was somehow causing the system to heat up though.

A few weeks ago, some time after that record temperature, while I was definitely running OS 10.5.5, a much more dramatic and disconcerting heat spike occurred. I was online at Guy Kawasaki’s blog, scrolling down a page (probably in Safari, but possibly Firefox) which contained many photos that Guy had taken. These were all still photos, not videos. I wasn’t pausing to look at most of them, just scrolling past them on my way to an earlier post lower down. I noticed the fans were running at a high speed. I brought up iStat just in time to see the temperature had reached 121° C (250° F) before the computer shut down, presumably due to overheating. As before, I have no way of knowing whether the temperature spike was the result of scrolling past many images, some intermittent, randomly occurring, hardware problem, or something unrelated to hardware or what I was doing on the computer at the time.

Then on election night, when I was halfway through watching an online video of John McCain’s concession speech, the MacBook Pro suddenly shut down again. I didn’t have a chance to observe the temperature before this happened, so I don’t know if it was a high temperature shutdown. Watching videos invariably causes the fans to speed up, so that wouldn’t have caught my attention. I had experienced one sudden shutdown before the one definitely associated with high temperature, and I had not considered high temperature as a likely cause then, not having observed the very high temperatures before. Now I have to suspect overheating as the cause of that earlier shutdown.

I’m trying to keep a closer eye on temperature now. I worry that having the temperature become high enough to cause a shutdown will eat into the expected lifetime of my machine. I’d be interested in hearing from anyone that has seen similarly high temperatures. Have others had shutdowns due to high temperatures? Use the link toward the upper right to send me an email. I’m weakly hoping it’s something that Apple will quietly fix in the 10.5.6 version. Until then, that 121° C reading is just one more way OS X soundly beats Vista.