This sounds like it's the same thing as the thermal pad mod for the M1 MacBook Air.
On the upside, you get better sustained performance and it lasts nearly just as long as the Pro, from what I recall. On the downside, it elevated the temperature of the backside aluminum to a high enough temperature to be able to cause burns (something like 80-90C). Not a huge issue if you always use it on a table or something, but if you truly use it as a 'lap' top, it'll be quite unpleasant.
> On the downside, it elevated the temperature of the backside aluminum to a high enough temperature to be able to cause burns (something like 80-90C). Not a huge issue if you always use it on a table or something
The bottom doesn't get that hot (90C would cause serious problems) but the additional heat is a downside to consider. Too many people are missing the point that Apple deliberately chose not to create a thermal bridge between the CPU and the case for this reason.
Apple made the right choice. The Air is designed for minimum size, maximum portability, and fanless operation. If you have use cases that benefit from extended 100% CPU load, get a larger MacBook Pro that has a cooling solution designed to sustain these thermal loads.
You're right, on looking back at the threads it was not nearly that hot. But it was elevated enough to cause issues. People reporting their laptops got uncomfortably hot, compared to stock.
Looks like the actual point where you start to get problems is quite low, somewhere around ~38C, so if the mod elevated temperatures even to 40-50C, you'd be in heavy discomfort or possible burn territory. This paper talks about skin lesions and burns happening around there: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3853603/
It doesn't have to be that hot to hurt. Every macbook I've tried under load since the original unibody has been unbearable on bare legs. IDC that its technically safe for the internals, it physically hurts at whatever temperature its at.
Low-temperature burns are a thing. If you are exposed to heat long enough, eventually it can get your skin hot enough to be burned. The same way you can slow-cooking meat.
leaving a cpu with no cooling solution is a recipe for cpu failure. see the xbox 360 red ring of death as a scenario where inadequate cooling caused issues for the buyers... this is poor engineering and customer hostile.
So you are saying its cooling strategy is to make the device slower for the user so it can cook itself until the ball joints on the CPU fail? Great design.
I've modded my M1 air and have seen and measured the improvements but I'm not sure if it's worth it.
Yes, it throttles less and things like renders and exports take less time but this machine already has about 10 minutes of "buffer" before it throttles and as a result you don't see the benefits before pushing the device beyond what's reasonable for an ultraportable laptop.
I would rarely do anything that lasts more than 10 minutes of full CPU/GPU load and when I do it would be something like half an hour and the thermal pad mod will give me back 5 minutes.
If I'm going to render something that takes hours, I would not do it on my machine that I use for everything. I would do it on some desktop with Nvidia graphics or I will rent a machine build for the task.
I don't think it's necessary.
On the other hand, I also modded my girlfriends 2020 Air with Core i5 and the improvements were much more noticeable. Unexpectedly, the battery life improved too.
The laptop that used to last 6 hours when watching videos now lasts about 8.
The fans were not spinning up to full blast at that use case bore the mod too, so I don't know how much the fans are responsible for the difference. My speculation is that the CPU is using less power when cooler due to the relationship between temperature and conductivity.
Maybe. That laptop is mostly used to watch Youtube and streaming movies and sometimes to do online shopping(she is using the company laptop for work, so no actual work done on this device since a year at least).
Static power (leakage) increases exponentially with temperature. Although, static power should be relatively small compared to dynamic power for TSMC's latest nodes.
I run my Air most of the time with the lid closed in a vertical stand and for this scenario the thermal pad mod brings the temperature under moderate load way down. Why does looking at LinkedIn or Redfin push the CPU up to 60C? Who knows but the thermal pad helps it not be worse.
However I did not follow a tutorial, I wasn't planning to mod that one but since I had leftover thermal pad, decided to give it a try.
Remember how YouTubers made a big deal about the "heat sink is not connected to a fan"? Well, they simply didn't know what they are talking about. The air flows from that heatsink even if the fan is at the other end of the laptop. Which means, you should be careful not to block the airflow when doing the mod. I put a thermal pad that is about half of the size of the heatsink.
So in my particular case I simply spin up a Linode or DO node when I will do something that will require hours of data processing. Maybe they are not the fastest options but at least lives my personal computer alone when processing.
There are also services that rent Macs or PCs with serious GPUs but I have no experience with those. AFAIK, for people who render 3D stuff there are render farms but I also don't have experience since it's not something I do professionally. When I render something that will take hours, I would ask for a remote desktop connection to my friends gaming PC.
> On the downside, it elevated the temperature of the backside aluminum to a high enough temperature to be able to cause burns (something like 80-90C).
as this will raise the overall operating temperature of the laptop's battery which is located adjacent in the chassis, I would consider this to be a very bad idea if you value:
a) longevity and cycle life of the battery
b) battery lifespan/runtime
c) lower likelihood of the battery catching on fire and going into thermal runaway on your lap or desk.
d) lower likelihood of the battery swelling up into something that looks like a pillow
there are very likely a number of solid reasons why the apple design engineers chose not to allow it to get this hot.
very solid physics/thermodynamics based science says that the hotter you run a lithium ion or similar battery, and for any extended periods of time, the more dangerous it is, and the worse it will be for the battery's overall lifespan and cycle depth/cycle life.
My M1 with thermal pad backside under heavy load gets to maximum 46°C compared to 37°C before. Everything above 42°C is uncomfortable on lap but it is not an issue for me at all as every time I need to run heavy load for long I'll be at my desk.
One of my biggest complaints with laptops is the heat and that I always end up putting like a book underneath so that my lap isn't in directly contact with the heat. If apple intended to keep the outer shell cooler, I will any day take it over the slightly higher performance that folks are getting with a thermal pad.
I kid you not, in the early Intel MacBookPro days the Genius Bar told me that my extremely hot MBP that I could not use on my lap due to the heat was not in fact a laptop computer but a notebook computer and by using it on my lap I was essentially holding it wrong. This was in or around 2005 IIRC.
A few companies ago, our IT dept's nannyware had a bug on OSX that was causing it to peg a CPU core at random. So, in engineering, we obviously just found a way to disable it. The IT guys were not amused. "It is against IT policy to disable this software" - yeah, well, it's against my policy to let your stuff burn my legs; get the bug fixed and I'll turn it back on.
IT can lean on the vendor to fix their shitty software.
If the head of IT doesn't want to do that, the department is dysfunctionally managed and does not have my sympathy.
Beyond that, I don't really care what policy is. While I generally don't care about company nannyware - after all, it's your machine - the line is drawn when you are literally burning my body. If you want me to use the device, it can't cause me physical harm.
Not really. It takes a sustained load over a long enough period of time to raise the temperature of the aluminum chassis to the point that it causes physical pain. If that's your use case, you have a point, but that's not most people's use cases, mine included.
That doesn't seem particularly unreasonable or even notable, other than the silly comment about the laptop vs. notebook label. Around that time all the laptops I remember got ridiculously warm. It was in the zeitgeist that men shouldn't use laptops on their lap because the heat could damage sperm quality. Everyone had those laptop trays with extra fans in them for using them on their lap.
Note that when the article says this outperforms the "M2 Pro", they mean the Macbook Pro with a M2 chip, not the actual
M2 Pro (sibling of the M2 Max) chips which have yet to be released.
I can't say I had any expectation given the mess that is the iDevices naming schemes (especially the ipads), but the Apple Silicon naming really is mind-boggingly bad. It's like the names are picked by a 12 years old with sub-par naming abilities.
Not trying to argue that the naming scheme is great, but I think they are trying to align it across multiple product lines, in which case it sorta makes sense.
They already have airpods use the same naming scheme, with the basic ones just being Airpods (without any suffix), then the next better option is Airpods Pro (the in-ear ones with active NC), and then their most expensive premium option is Airpods Max (large over the ear headphones with active NC, dial, and ability to still use them in wired mode with standard 3.5mm aux). The hierarchy is the same as with M-chips, with the most basic to the most premium being (no-suffix)=>Pro=>Max.
As a sidenote, I partially blame whoever wrote the article title for the confusion in this thread. They used proper name for M2 Macbook Air, but didn't use M2 Macbook Pro for the MBP. Dropping the "Macbook" part served exactly no purpose but to (most likely unintentionally) confuse the reader.
Wow, so the "MacBook Pro with an M2 Pro" is the name we should use for that machine which is yet to be released? And this is referring to a Macbook Pro with a M2.
Not news, it's the same chip but different cooling. This hack "fixes" (hacks) the cooling to make it equal.
To be clear, the real reason Apple don't do this themselves, is because there are legal regulations preventing them from selling products that are any hotter to the touch. According to the IEC, metal contact surfaces on machines are considered unsafe above 55.5C. And unmodded, Apple's notebooks already scrape up against that upper limit. With the mod, they go quite a bit over it — well into "causes pain to touch" territory. (See: https://www.youtube.com/watch?v=ghDvyItIHTY&t=278s)
The stupid & obvious & I-wish-us-idiot-laymen-could-claim-prior-art (not-that-that-helps-anymore) answer is to put a temp sensor on the case too.
Just not thermally bridging is a fine stupid answer. But if someone puts their laptop onto a laptop cooling stand, heck yes it would be fantastic to reap a 2x+ benefit. This is, in my view, as much a product choice to make sure Air does not encroach upon better territory as anything else. Companies like Intel & AMD have been way behind comparatively to Apple in mobile chips, but the old-giant competitors at least typically allow a well cooled chip to work better, which, in my view, is a product not technical decision made here: the decision to use less cooling.
That said, there is some (I'd wager modest) benefit to using the case as a thermal insulator rather than dissipator for the average user.
I find the overheating controversy of the fanless M2 MacBook Air to be bizarre. If you open up the M2 MacBook Air and take a look inside, it looks almost identical to the iPad Pro. The M2 MacBook Air is clearly designed to be the clamshell version of the iPad Pro. It's not meant to do heavy workloads for long periods of time. Apple wants you to upgrade to the thicker and heavier 14" and 16" MacBook Pro's with fans for those kind of heavy tasks.
Do most people understand this, though? I would have assumed it was chiefly about a difference in size - that the main tradeoff would be reduced screen real estate in exchange for a lighter weight and smaller form factor.
I suspect that anyone with even a passing awareness of the Mac product line and the term "performance benchmarks" would know that performance has long been one of the key distinguishing characteristics of the Air and Pro lines.
Sure, although there's a bit of dissonance between "this is a great laptop because it uses the M2 which is our fastest CPU ever" and "you shouldn't be complaining about performance on an entry level system".
A high sky Skylake ultrabook from 7 years ago with maybe 8gb of memory if it was higher spec is fuck slow with a bad battery life and you can absolutely notice the difference even if you're capable of ignoring it. The Intel HD graphics GPU on these laptops is also a real problem.
A good laptop does make a difference when visiting some javascript monstrosity on the internet, I'm not saying it's good value, but if you have the money, why not buy a MacBook Air over a Chromebook?
I agree with battery life but I honestly doubt people could see a performance difference between a good laptop from 7 tears ago and a new MacBook. Of course if you benchmark them you will see it easily. But just browsing the web and doing some mail? I doubt it.
In that sense I feel like buying a powerful laptop for browsing and mail is a bit like buying a Ferrari. Sure your car can go fast but you won't ever use it.
There's a very good reason the bottom panel isn't part of the cooling system, as a 70C panel sitting on one's lap could be indicated in infertility, long before it causes any burns or other obvious discomfort.
If the Air had a Surface Book like design where the heat could radiate behind the display, this would be a different affair. It doesn't, so that heat will go to your legs and what's between them. Beyond just being uncomfortable, this would be a liability and press issue that no one at any laptop company wants to deal with.
Do you mean permanent infertility, or just for the sperm that are currently present? I have to imagine it's the latter, which is not a big deal for anyone not looking to conceive. If there were persistent effects (even short of full infertility), that could be a much more serious issue.
No permanent damage is your threshold for what is acceptable? There is plenty of discomfort long before we get to permanent damage. Are you really arguing that companies should base their product designs on whether or not the problems they create for their users are permanent or not? No company with any hope of success would ever use such a criteria.
> No permanent damage is your threshold for what is acceptable?
Not the person you are replying to, but it depends on what kind of damage. If it left painful burns or something actually bothersome, then I wouldn't like it, no.
If it is just gonna make me unable to have kids until I stop putting the device on my lap, then I am totally ok with that. I currently don't want kids, so this does nothing to me. And if I change my mind later, I can just alter my device usage accordingly, since it isn't permanent.
So someone who is able to install custom heatsinks on an expensive electronic is also going to be rendering long professional videos (to get it hot) and keep that +150F degree laptop on their lap long enough to cook their goods?
Note that thermal pads, although being a lot better than nothing, perform worse than thermal paste or thermal glue. If space allows it, gluing a piece of copper or aluminium on each chip would increase the chip's thermal mass significantly, slowing down the speed at which the chips changes its temperature.
Then one could add a thinner thermal pad to achieve even better thermal transfer with the laptop plate.
I’ve been playing COD Warzone on my 2018 MPB 15”, I kept getting stuck at 17-30 FPS, so I slapped a big ol fan on the back of the computer to help circulate the air around it, and on the back cover. Solid 60 FPS now.
Should be sufficient for a while, thermal throttling is a real thing.
This reminds me of an incident a long time ago when we had issues with Compaq 386’s overheating. I came back from holiday to be told that they had solved it by adding a bigger fan. When I finally saw the offending machines they had their covers off and 15’ office fans pointing down onto the motherboard. Did the job though.
I had an xbox 360 that would always overheat and red ring itself. Eventually I realized the window fan I owned had almost the same curve angle as the 360 case. I built a little stand out of some books to hold it flat upright with the air blowing straight up, with the xbox laid horizontally on top of it. Air was just dumping through the vents in the case and that xbox never red ringed again. Wasn't designed for it but it worked better than the manufactured solution evidently.
People never realize that you can do the thermal pad "mod" to the 13" M2 Pro as well, to make it reach beyond the speeds of the M2 air to get closer to the 14" speeds.
And you can do the mod to the 14/16" laptops as well - basically a thermal version of an overclock.
The thermal pad mod was applied on the 2019 Macbook Pro 16" intel model to great success before M1 was even a thing.
I did this to my long suffering 2015 MacBook Pro, which always had significant thermal problems. It worked pretty well to keep it from overheating, but it’s no longer safe to use the computer on my actual lap as the bottom gets skin-burningly hot in minutes.
Rip off the thick cardboard backing of a notebook and tape it under there with some pennies to form a little bit of an airgap. Boom. Free slim profile laptop stand that you can keep on all the time. Who looks at the bottom of the computer anyhow?
Seems a bit improbable that a company capable of excellent engineering choices forgets about the obvious - measure temp (100+) and realize hmmm maybe we need to disperse that bit better with this easy solution
Segmentation in the sense that: this laptop is not designed for the workloads that produce 100+ temps.
That's not an oversight, that's an engineering tradeoff to lower the weight and thickness for the workloads that it is designed for: day-to-day usage by the average person (i.e. no video render, no big project compiling).
>that's an engineering tradeoff to lower the weight and thickness
huh?
This mod doesn't seem to change thickness at all and 3% weight gain for a gigantic jump in performance under load barely counts as a trade-off....more like a no-brainer.
except for the inevitable "this laptop is uncomfortable to use" "this laptop causes infertility" etc; etc;
If you want sustained performance (greater than 5 minutes of sustained load) then just don't get this laptop. For bursty workloads (as is standard for ultraportables) it's perfectly fine, you'll never even notice there was a thermal cut-off.
As others have mention in the comments here, it’s not about thickness of the pads it’s about the new surface temperature of the chassis. It gets too hot to be at all comfortable.
If you need sustained workloads, get the laptop designed for sustained workloads.
It's either intentional in terms of deliberately neutering the non-pro model (something we see all the time in computers and processors) or intentional in terms of not wanting to make people feel uncomfortable with the heat
For anyone wondering why Apple didn't ship it out of the factory like this....
There are laws and regulations in most of the world about the maximum surface temperature that devices may hit during operation. They usually vary by material. Since the MacBook is metal, the maximum surface temperature usually can't be above 45C or so to avoid burning the user.
I'd bet with this mod, the surface of the laptop gets much hotter than that, so it would be illegal to sell.
I suspect no, as if you look at ifixit's teardown they show there's actually a thermal shield in place, likely to prevent your lap from being exposed to the higher temps: https://youtu.be/NjP-aAhHhnE?t=122
The elegance of the fix makes me wonder if the original design had a thermal pad in that location, but a lawyer decided they could avoid more liability by crippling the CPU speed instead of burning laps.
Assuming these results are legit (as they seem to be), did Apple just not do this because it cuts the performance differential between the M2 MBA and the M1 MBPs too much?
Many of these Macbook thermal mods use the case more aggressively as a heatsink, and can end up making the enclosure hot enough to burn you if used as a laptop.
They probably could add some case temperature sensors and throttle once the case gets hot enough.
Would still gain a lot of performance; outside of benchmarks most people don’t run their computers hard enough to need full boost for minutes at a time.
Running the case this hot will degrade the battery significantly faster, hot battery reduces short term capacity and hot battery reduces lifetime capacity. MacBook(2015) has similar issues.
FWIW, the default scaling settings have no problem letting the M2 Macbook Air hit 80-90 Celsius by default, it will just heavily start throttling the performance cores to prevent overheating, which better cooling helps mitigate.
The CPU heating 80-90C is very different from the laptop shell hitting 80C. "Better cooling" on a fanless computer means moving the heat out into your lap.
It has a non-negligable impact on surface temperature. Even on actively-cooled Macs I've owned in the past, the MacOS governor is way too lenient with letting the CPU clock up. Having an 80c+ internal temp made the palmrests too warm to comfortably use, for me at least. I don't really see how removing the fans is going to help reduce the surface temperature, especially with a material as thermally conductive as aluminum.
Isn't the slow storage issue only on the base (256GB) model? I don't know which model these benchmarks use, but it would be surprising — and very dishonest — if he was using an MBP with slower storage and then chose an MBA with fast storage (the base model MBA has the same issue as the MBP).
Until Apple decides to lower their prices for the Air M2, I'll wait with my upgrade from M1. I own an Air M1 with 8GB and I was thinking to buy the newer version until I saw the pricing.
Heck, the difference between the M1 with 16GB RAM and 512 GB storage and a M1 14" MPB with the same amount of RAM and storage is around 60 euros (from a local reseller). I haven't bought the MBP PRO because I find it too heavy for my personal usage (I also have a company MBP 16" Intel that will be replaced next month with an M1 Max version).
so if you add thermal pads to the Macbook Pro with the M2? its very confusing that this article is actually about two devices with the same chipset, the Macbook air and Macbook pro. It seemed like they were referring to a different unreleased superior chip: the M2 Pro
The reason these are called "portable computers" and not "laptops" has to do with the electromagnetic radiation generated from onboard wireless COMMs (e.g. WiFi).
As this type of machine should already NOT be sitting atop a human, I do not see an issue with directing the excess heat to the exterior shell/heatsink.
Do you have a reputable source that the levels of EM radiation from laptops is harmful when placed on laps but not when placed on desks in front of you?
Anyone else feel that Apple has completely screwed the pooch on the marketing here? I feel this is just going to end up in a mess of confusion of M1/M2/M3 with superfluous adjectives.
I think it doesn't help that the computers are called Pro as well, so you could have a MacBook Pro with M1 Max, etc.
I mean there was another comment on this thread that had to clarify that when they said "M2 Pro" they had meant the "MacBook Pro with M2" not a future "M2 Pro" chip.
The marketing seems pretty straightforward? M1/M2/M3 (and their sub-variants) and fan/no-fan are the two performance aspects, and then you just decide whether you want a 13"/14"/16".
The 13" is substantially different from the 14"/16" though. It's a carryover of the previous design (bigger bezels, no notch) and has the lower tier processor with 4+4 performance and efficiency CPU core split. The 14" and 16" have a 8+2 CPU cores instead.
EDIT: other differences include mini-LED backlight, 120 hz refresh rate, 2x the base RAM, 4x the maximum RAM, function keys (instead of touch bar), support for 3 external displays (instead of 1), HDMI, SD card slot, magsafe, and faster charging
Much more of a choice to make than "do I want a fan or not" if you include the 14" and 16". That's pretty accurate between the Air and 13" Pro though.
I think the grandparent commenter is illustrating how confusing this is. To break it down, here are the chips and laptop models:
- M1 Macbook Air (old)
- M1 Macbook Pro 13" (old)
- M1 Pro Macbook Pro 14" (or M1 Max)
- M1 Pro Macbook Pro 16" (or M1 Max)
- M2 Macbook Air
- M2 Macbook Pro 13"
Note that the "Pro" modifier can be applied to both the laptop and to the chip. An M1 Pro or M1 Max is significantly more powerful than an M1 and still more powerful than an M2. An M2 Pro or M2 Max _chip_ doesn't yet exist, though the linked article's title confusingly implies it does. The thermal pad mod just makes the M2 Macbook Air perform as well as the M2 Macbook Pro 13", but it doesn't make it perform as well as the M1 Pro/Max Macbook Pro 14"/16". Benchmarks: https://browser.geekbench.com/mac-benchmarks
I'm not confused.. but as demonstrated in this thread, confusion exists amongst users.
Also your example sort of made my point. The names "threadripper 3990x" and "ryzen 5500" are pretty meaningless by themselves and from those names alone there's no implied relationship about which one is newer/faster. This is a good thing! However, "M2 Macbook Pro" vs "M1 Pro Macbook Pro" could be naively interpreted incorrectly.
I think the issue is that there is some overlap in performance between a fanless M2 and a fanned (is that a word?) M1.
Also, Apple doesn't exactly advertise the fan status of each laptop. Currently, only the MBPs have fans, but in the past MBAs had fans also. But most people don't know the fan status of Apple's lineup, so this isn't really part of their marketing messaging.
It's not straightforward to me personally. Look at the photos on the Apple store, I don't even know what these laptops look like, let alone which one to pick.
Add in the SSD issues and the info-sparse spec list and I really can't tell and the whole S/Pro/Plus/Max/?? situation. I wish they were clearer
> Look at the photos on the Apple store, I don't even know what these laptops look like
Browsing on my phone, apple.com > store > Mac[1], I see a carousel showing the front of each Mac model (oddly showing the older MacBook Air first, I’d guess because it’s the least expensive?). Tapping each model, a view for that model shows up with a carousel showing additional angles/perspectives. Granted this isn’t the most obvious navigation from the home page, and the individual products’ landing/marketing pages too frequently bury useful images.
> Add in the SSD issues and the info-sparse spec list and I really can't tell and the whole S/Pro/Plus/Max/?? situation. I wish they were clearer
If I go to Compare Mac Models[2], the spec comparisons don’t seem especially sparse. Below the fold details get more specific about the chips. Granted they’re mostly differentiated by core counts (and, oddly, memory bandwidth). The page also enumerates all configuration options for each model.
I do agree they should be more upfront about SSD performance by configuration.
Oh wow, I didn't even find the first page when on the apple site. Thanks for this! I was navigating Apple > Mac > Buy.
I was looking at the pages for the specific laptops (which, as far as I can tell, only have the front-facing photos.) The spec situation is still confusing (took me awhile to figure out the $1200 MBAs and the $1500 MBAs were two configs of the same model; "Select" essentially takes you to the same place, which was very confusing.)
I had a black 13" MacBook back when those came out. I loved that machine, it was the perfect size and looked so cool. Then someone broke into my car after work and stole it. I'm still bitter about that.
Looks pretty straightforward to me: higher number - better processor. Now between M1 Pro, Max and Ultra how can you tell which one is supposed to be better ? :)
I feel like Apple lost a golden opportunity to add these pads themselves but then thermal throttle this machine in the firmware UNLESS you purchase a $199 magnetic heatsink/docking station for the underside.
Seems like something they would have done if only they had thought of the idea.
they could have done it if they thought that there was a problem for the people buying the Air. If those people are frequently doing 8K Final Cut Pro renders, then this kind of modification might make sense. If the Air buyers are browsing the web, doing photo edits, and doing basic programming, there is no need because those tasks don't push it into the heat limits.
Of course, there is the problem that those mods cause the case to heat up past the limits that EU safety regulations allow, but they just don't need to sell it in the EU then?
This seems like such low-hanging fruit, though. It wouldn't take very much at all - just a single extra NFC chip, and some code to allow the chip to run at full TDP while plugged in + on an approved cooling pad.
The benefits are HUGE - plenty of people want small laptops that they can use on the go, but most laptops spend most of their time docked.
How huge are the benefits, really? This doesn't affect normal operations. The laptop stays cool during most of the things you would do on a laptop. The only time it hits the thermal limits are during large batch operations involving both the cpu and the gpu. Even then, it still does the work but has to slow down by only 10-20%.
On the upside, you get better sustained performance and it lasts nearly just as long as the Pro, from what I recall. On the downside, it elevated the temperature of the backside aluminum to a high enough temperature to be able to cause burns (something like 80-90C). Not a huge issue if you always use it on a table or something, but if you truly use it as a 'lap' top, it'll be quite unpleasant.