Skip to main content

Properly using Thermal Paste to keep your MacBook Cool

I hear a lot of people talking about how their MacBook is too hot.   They look at on-line forums and see that their MacBook is running at 83 C and get very concerned.  They learn from the forums that they need to re-apply the thermal paste to keep their computer cool, but virtually all the forums participants are amateur idiots that offer ridiculous procedures that are likely to damage your computer.

This article is the right way to address this problem.  

First, let's talk about why your computer is running so hot.

Computer CPUs get hot.  They're designed to get hot, consuming many watts in a very small surface area.  Ever touch a 25 watt light bulb that's been on for 5 minutes?  It will be painfully hot.  Take that 25 watts and put it in a much smaller package (think halogen), and it will be MUCH hotter.  That's a CPU - a 25 watt device in a very small package.

CPU manufacturers put temperature probes inside a CPU not so that you can look at the temperature, but so that the computer can regulate its own heat.  No heat sink is going to prevent that CPU from getting hot.  Instead, a heat sink is designed to take that heat and spread it across a larger surface.  Now if that heat sink was huge, you'd be done.  But a laptop is small, so a fan is then used to blow  room temperature air over the heat sink.

Your laptop has fan circuitry that is designed to regulate its temperature.  The fan's cooling ability is based on the ambient air temperature and airflow.  If the computer is feeling hot, it will spin up the fans to exhaust heat.  The amount of cooling is based on airflow and the temperature of the air going into the machine.

So, what about thermal paste?

Thermal paste is simply some heat conducting goop that helps the heat to move from the CPU to the heat sink.  Applying thermal paste is as simple as scribbling with crayons.  And it will last far longer than the life of any machine.  And therefore, "poorly applied thermal paste" or "worn out thermal paste" simply doesn't happen.

All that said, computers can get too hot, particularly when they get old.  Why?  It is almost always due to dust clogging up the airways of your computer, preventing the fans from blowing air over the heat sink.  When a modern computer gets too hot, it will automatically power off.  If you have that kind of behavior, the right response with your computer is to see if you need to de-dust the air passages. Another possibility is that the fan has failed.

So, in conclusion, leave the thermal paste ALONE.  Ignore the forums, as they are filled with idiots and shills that market stupidly overpriced thermal paste.  Let your Mac regulate its own temperature.  If the fan is spinning too hard, it is because you have a runaway process, or because your computer is full of dust.

Popular posts from this blog

Sodastream Carbonator Leakage, Usage, and Weight

SodaStream 60L "Carbonator" CO2 cylinders have a specific weight when empty, plus about 410 or so grams for the CO2 they should have when they're "full".  A little while ago I went to buy a replacement Carbonator from my local hardware store. The dealer pulled a new Carbonator out of the box and sensed it was lighter than usual.  He put the "light" Carbonator in the "empty" pile and sold me a different one.  At that moment I concluded that it would be smart of me to weigh both new and empty SodaStream carbonators.  Here are the results. Weighing a SodaStream Carbonator - for both Science and Consumer Protection.       The dealer told me that sometimes the carbonators leak after they leave the SodaStream filling facility.  That means there could be an opportunity for customers like me to get ripped off! The SodaStream cylinders I buy claim to have a net product weight of 410 grams - and that means that a full Soda Stream Carbonator shou

Fixing a SodaStream Jet, part 1: Disassembly Guide

I've had my SodaStream Jet for years, and once in a while something has gone wrong. Disassembly is the first step to repair.  Start with this article to see how to disassemble the SodaStream, and then once you have that down, scroll through my other articles to see how I repaired specfic SodaStream problems. SodaStream Jet Disassembly Guide Tools Required Flat head screwdriver Phillips head screwdriver 1. Remove the Carbonator.  Duh. 2. Remove the black panel lever The front big black tilt lever needs to be removed first. Removing this panel is tricky, but it isn't impossible. Looking up at the bottom of the black panel, there are two tabs, one on the left and one on the right. These tabs fully secure the panel in place. The trick is to use a flat-head screwdriver under the plastic to gently lever the tabs out of the way.  Note in the pictures how I approach these tabs with my screwdriver.  I usually release the left side first, and then I release the right

Fixing my Wahl 9918 Groomsman Beard and Mustache Trimmer

Not everyone would bother repairing a $25 beard trimmer, but why not fix something for under $5 instead of spending another $25? My  Wahl 9918 Groomsman Beard and Mustache Trimmer  has admirably performed its beauty duty for many years, but the time came when the battery just wasn't holding a charge any more.  Most people would just put the trimmer in the trash and buy a new one, but I figured I could repair my otherwise excellent Wahl and save some money. In fact, even high priced trimmer and rotary shaver brands, like Norelco and Remington, can be easily repaired using a process similar to the one I used to fix my Wahl.  Read on to find out how. I opened up the Wahl by popping off the black plastic faceplate with a tiny flathead screwdriver, which revealed two screws.  By removing the two screws I was able to easily open up the unit, revealing the guts of the device. Backplate off, Revealing the screws The internals are rather simple: a motor, a simple circuit boar

Fixing a SodaStream Jet, Repair #2 - Broken Fill Button

My Soda Stream Jet's fill button broke, which means I can not longer carbonate water by pressing the pushbutton. This caused all sorts of grief in my household. Here is how I managed to repair my Jet to give it another 10 years of life (hopefully). First, a look at the button The fill button on the top of the SodaStream is actually a simple lever. Pressing down on the button moves a pin that does the actual work of pressing open the Carbonator's valve. Unfortunately, the axis point is fairly thin and can see a lot of stress. That's where my Soda Stream button cracked. [ I think the usage tip here is "don't over-press the button like a gorilla, it doesn't do anything but put high stress on the button."] Cracked levering point of the button The Pesky Lever Retaining Pin The Fix It was pretty easy for me to replace the button: Take off the back of the Soda Stream and remove the carbonator. Push out the the button lever's steel retaining pin. This takes qu

MacBook: burnt out magsafe connector repair

My MacBook (A1342 model from 2009-2010) stopped working, thanks to a cheap knockoff magsafe charger. The magsafe connector looked burnt with heat-distorted melted plastic and some black carbon surfaces.  Plugging in the charger resulted in no lights and no action.  My MacBook was dead. First I tried to clean up the connector with some Q-Tips, tooth picks and solvent, but that did little, as seen in this "after" picture (below).   The heat generated by the aftermarket charger permanently deformed and distorted the MacBook's magsafe connector.  Clearly the damage was significant. Burnt Magsafe Connector - Replacement Required! Looking at iFixIt , I determined that it would not be difficult to replace only the magsafe connector with the right tools.  I hoped and prayed that the problem was isolated to the connector assembly and not the logic board. I bought a replacement magsafe connector assembly (available from Amazon) for under $20 and started to replace it by

Dustbuster Switch Repair

My Dustbuster vacuum - a CHV-1410, gets a lot of use.  We use it several times per day, every day.  It is a workhorse. Sadly, it was becoming unreliable.  It would be fully charged, and I'd hit the switch and maybe it would begin to start and then stop, or it would lurch and stop - or maybe it would do nothing. My CHV-1410 had a broken switch At first I thought it was the battery, but then I found that by carefully wiggling the switch I was sometimes able to get the vacuum to work.  All that on-off action over the years made the switch unreliable. Instead of throwing away an otherwise perfectly good vacuum, I decided to replace the worn switch.  It's an easy and worthwhile repair with the right part. The one special part needed: A specific $5 Switch There seems to be two types of switches used in these, based on the charging mechanism: For the Lithium models (CHV-1410L and similar), I notice that there are only two conductors are attached to the switch: one for &q

Other Posts

Show more