Dear Lifehacker, My laptop is hotter than the surface of the sun. No, seriously. It's a tad old, but I'm not ready to get rid of it yet. Unfortunately I can't use it without feeling like it's going solar on my thighs. Is this something I should be worried about, and how can I fix it? Sincerely, Combusting Computer
Ah, the classic, too-hot-for-your-lap laptop. It's something almost every laptop owner has experienced at one time or another. When you cram that many computer parts into such a small space, without a lot of room for airflow, things are going to get hot. Couple that with a heat-conducting case and you've got a computer you could probably cook an egg on. It doesn't necessarily mean your computer is having problems, but either way, there are a few things you can do about it.
Determine Whether Your Computer Is Overheating or Just Hot
Laptops get hot. It's what they do. However, if your laptop is shutting down, suffering from the blue screen of death or experiencing serious slowdowns, then you have a much bigger problem on your hands. In this case, you should probably take it in and get it repaired, if possible.
Macs have a built-in failsafe for heat problems; they'll turn off before they reach unsafe temperatures. So it's pretty easy to tell when your computer is actually overheating, because it'll shut down unexpectedly. Windows computers don't always have this, but you can install something like the Core Temp CPU monitor to get it. Check your laptop's manual for safe temperature limits, subtract about 10C, then plug that value into Core Temp under Options > Overheat Protection. You can set your computer to give you a popup message or go to sleep if it ever reaches unsafe temperatures. If it doesn't ever notify you, it probably isn't overheating, and your problem is merely a matter of comfort.
How to Keep Your Laptop Cool
Even if your computer isn't reaching overheating temperatures, it can be hot to the touch, which isn't always ideal. Here are a few things you can do to keep things running cooler.
Check (and Clean) Your Fans
When you feel your computer getting hot, put your hand next to the computer's fan vents. If you feel hot air blowing out of them, then your fan is working, but if you only feel a little bit of air, it could be your fan is built up with dust or is otherwise not working. If you're comfortable opening up your computer, you can unscrew the case, find the fan and blow it out with some compressed air (or replace it, if it's just broken completely).
Keep It Out of Hot Weather Remember that direct sunlight and hot ambient temperatures will help contribute to your laptop's heat. Even if your computer doesn't regularly overheat, temperatures over 35C are likely to cause problems, from damaging your battery to making your hard drive expand and more. When possible, keep it in the shade and out of the sweltering heat.
Use a Lap Desk
Your laptop is designed to sit on a flat surface. Those little rubber feet on the bottom are supposed to lift it off the ground just enough to get a bit of airflow underneath the computer, and when you put your laptop on your lap, you restrict that airflow, transferring all that heat to your legs instead (ouch). This is one of the reasons most manufacturers replaced the phrase "laptop" with "notebook" - they don't want to encourage you to do something that could be dangerous.
Sitting Indian style can help, but a much better solution is to get a lap desk. They don't need to be expensive; we've shared a ton of DIY options here before, and they'll not only keep your computer cool, but they'll keep your legs from getting burned, too. (And, with all that airflow, it might keep your fans from running at full speed, keeping everything a bit quieter.)
Control Your Fan Speeds
While the above should be sufficient, you can take slightly more intense measures to cool your machine off, if desired. A great way to keep everything cool is to install a program like SpeedFan. You can read more about fine-tuning your fan control in this how-to. Just know that it isn't necessary to keep your computer safe, but is good if you'd rather keep your computer loud and cool rather than quiet and hot to the touch.
Keep an Eye on Intense Processes
Lastly, you can keep your computer cool by keeping those CPU-intense processes to a minimum. Whenever you load up a website with Flash, for instance, your CPU is going to start working harder, getting hotter and running your fans more. You can mediate this by using previously mentioned FlashBlock in your browser, so you only turn on Flash videos when you actually want them. Computer games and video encoding programs require a lot of juice from your CPU, so it's best to use these on a desktop machine (if you have one) or maybe at night, when you aren't as worried about touching your laptop case.
Also, keep an eye out for runaway processes. If your fans start to spin up loudly and there isn't an obvious reason why, open up the task manager to see if something else might be hogging your CPU. On a Windows machine, you can do this by pressing Ctrl+Shift+Esc, and if you're on a Mac, open up Activity Monitor under /Applications/Utilities. Check the Processes tab and see if anything is using your CPU — usually, anything in the double digits is probably your culprit.
Hopefully this helps you get your laptop to a more comfortable temperature, but remember: if it isn't shutting down or causing problems, the main problem is probably that you're using your laptop on your lap, which you shouldn't be doing. These tips will help you cool it down when you need to, but the most important thing is to keep it away from your body, even if you have a layer of clothes in between you and the computer. Good luck!
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