Lately my Mac Pro has been crashing and freezing with greater regularity. From prior experience with computers crashing, and it being a particularly hot summer in London, I had a hunch it was heat related.
Weird artifacts on the monitor display (strange green and pink blocks and lines) clued me in that it might be the Radeon X1900 display card that was the cause of the overheating, and a bit of searching around on the Internet showed that this card has something of a reputation for overheating. The solutions people talk about, all seem to revolve around removing fluff from the fan ingest (did that), purchasing after market coolers (not cheap and quite complicated) or buying a new card (even more expensive). I wanted to find something else.
The first step was to confirm that it was heat related. I shut down the computer, opened the case, and let the computer cool down for an hour. When I started it up again the computer lasted longer before crashing than normal. A good clue.
I went looking for a way to see what the temperature actually was inside my Mac Pro. There are several methods for doing this but I found a wonderful free utility called Temperature Monitor. This shows you the temperature for many points within the machine and can graph them over time. A very useful tool indeed.
Although Temperature Monitor did not show a specific temperature reading for the graphics card itself, two readings in particular seemed high and are indeed physically close to the graphics card – the Northbridge and Memory Module B2. Both were up around 80 degrees C which is definitely a little hot.
I used another free utility, the brilliant SMCFanControl to adjust the speed of the fans within the computer. While running the history graph feature of Temperature Monitor I first turned all the fans up to full and immediately saw nearly all temperature readings within the Mac Pro go down. It was amazing to watch. After some fiddling I set the PCIe/HDD fan to a minimum speed of 1700 rpm which brought the Northbridge and Memory Module B2 temps consistently down under 70 degrees. I left the other fans in the end at their default settings.
Since then I haven’t had a single crash and I’ve not spent a penny. I’ve created different profiles within SMCFanControl (Normal, 1/2 cool down, 3/4 cool down, full cool down) and can instantly change the speed of the fans at will, depending on the ambient temperature.
Now if only I could get a speed increase utility for my air conditioner…
Excellent post, as usual you reveal great information to make life much better at no cost. Can I get a version of SMCFanControl for my brain?
This definitely works — I have a Mac Pro dual quad that has been crash prone since 10.5.2 getting progressively worse thru 10.5.7 — worked fine with 10.5.1 — would only run for 1-2 hrs at a time — I went through a zillion other options before seeing this article – I sped up the fans and haven’t had a problem since. I wonder if it’s not the graphics card – I was starting to get odd mouse and keyboard problems too — the ATI Radeon 2600 firmware update with 10.5.2 may be a cause, can’t see the card fan operating — also I’m guessing the newer op systems may be placing a larger load on the system — ??
Good tools regardless – thanks for the info
Thanks for the hint; definitely helped me bringing temps down in my MacPro early 2008, 16GB mem and 4x450GB SAS @15000rpm
Thanks for the great post from last year. I am wondering though if making the fans work hard like this will cause them to wear out quicker. The daily – and several times a day if the computer is on for extended periods – heating up and cooling down – can this be good for the Mac? This is good as a temporary solution, but I am wondering why my Mac – Tiger 10.4.11 – has suddenly started heating up like this (in the evenings too, when external temperatures are not high), and how to tackle this root cause whatever it may be. Unlike your problem, in my Mac all the positions can rise in temperature to between 60 and 68 degrees, other than the SMART disc, which stays in the mid. 30’s. I’m using the temp monitor application to know this and the fan control, but do you have any other ideas?
Simon, thanks for your comment. You are correct that it is generally going to lead to quicker wear of the fans by running them at a higher speed. The worst that can happen however is that the fan dies (or gets so noisy) that it needs to be replaced. For me this was a better option than replacing the more expensive video card, for a problem that only manifested itself in my case in the high heat of summer. I have in the two years since writing this article subsequently replaced the video card which was the root cause of my problem. In your case it’s hard to say what is the cause, but fluff buildup, a failed fan or badly mounted heatsink are the most likely culprits. Good luck.
I have a Mac Book Pro Mid 2010. The present moment I am using OS 10.6.8 snow leopard and the problem that I was encountering is the spinning beach ball of death and the computer freezing up. The first thing I did was research Google and found good information. Removing the bottom cover, I then proceeded to use a soft artist paint brush and clean the fins of both fans and blow with compressed air until the fans were completely clean of dust as well the vents. The inside of the bottom cover was wiped clean, then blown with compressed air to remove any dust residue. I then installed the cover and downloaded HD fan control, setting the fan speeds at 2000 rpm.
My hope turned to despair when I found myself back at the beach and the water was freezing. Sitting in my chair, the only conclusion I could up with was temperature problems. It was when I looked over at my early 2008 I mac 24in which has the same problems which took out my logic board that I came up with the solution. The I mac’s case is used as a heat sink to help dissipate heat which I have to say is a very poor design. Two of my friends own PC laptops which have vents on the bottom of their computers and are using USB fan pads to keep them cool. The Mac Book Pro has a solid aluminum bottom cover with no air vents as well as the main chassis being aluminum and what I now have is a laptop being used as a heat sink causing more heat build up. The fans in the computer were not designed to overcome this heat problem only to do the job they were intended. What is my next alternative? That being the question, I then placed a 6in. house fan behind the screen tilting down so air would blow under the computer helping to cool it with very little affect. TEMPERATURE! TEMPERATURE! TEMPERATURE! Then the light bulb lit up in my brain (if that’s what you call it) and I found my problem. AIRLOCK
SOLUTION: Take notice that when the laptop is on your computer tabletop, there is an air gap of about one sixteenth of an inch and the air become very warm. This air becomes trapped not allowing cool air to enter. I then did a mock test by placing 4 covers from pill bottles, one in each corner of the laptop which raised my computer allowing me an air gap of one half inch. The air from the 6 in. fan now circulated under the computer. The repair would require 4 rubber footpads one half inch in height and remove the old pads and crazy glue the new ones on the bottom.
THE TEST: I opened YOU TUBE, I Tunes, I Photo, and played a movie all at the same time and the temperature rose to 48.6C from 39.7C. When I touch the the laptop, it like it’s not even powered up with no heat whatsoever.
I am not keen on the idea of increasing my fan speeds. It’s cheaper to replace a 6in. house fan from WALL- MART then your computer fans. You can then adjust your fan speeds accordingly.
I hope this has been helpful.
Hey Stan, thanks for your helpful comment.
I’ve recently updated the links above since this article is still popular six years on (!) The good news is that both utilities mentioned above are still available as of early 2015, although it appears Temperature Monitor has been superseded by a new paid utility called Hardware Monitor. The original Temperature Monitor is still available at the link above however. Do love it when software companies do that…
Interesting story on how you fixed your mac book pro from overheating. You don’t need to run your fans at full blast though if you don’t want. If you want here is a link with a lot more tricks and tips culled from many places to fix your mac book pro from overheating without needing to focus only on the fans
Hi There! You have no idea how helpful this has been! My mac wasn’t working and its been stressing me out for days! I spoke to apple customer service last night, and because the fan program isn’t apple-owned, they probably aren’t allowed to talk about it! Thanks so much!
I know this is an old post, but I just came across it about a month ago. My 24 inch iMac was crashing/freezing at least once a day, and often twice a day or more. I was getting the same artifacts as described in the article. I was getting ready to replace the graphics card (which I was dreading) when I stumbled onto this article. I downloaded SMCFanControl just before Christmas 2015 and I have not had a single freeze or heat issue since. My trusty 2009 24″ iMac is working beautifully again. Thanks for the heads up!
I tried SMCFan, removed dirts from MacBook Pro Hardwares but nothing works to reduce the heat!!!!
Wow, great post man, thank you…really seems to help with the temp and fan speed control apps!