Early 2011 MacBook Pro- The thermal paste discussion.

Question

It is my goal to clear up the questions and concerns Apple customers have been having regarding heat or fan related concerns with Early 2011 MacBook Pros. If your MacBook Pro was produced within the last few months the thermal issue has been resolved and it will likely not be in issue for you. If you are still wondering if your computer is effected or what the real issue is keep reading.
The MacBook Cools itself by 2 main methods: active and passive. The active cooling is via a fan that blows air through a heatsync and into a tube called a heat pipe which leads to the back of the computer where the hot air is discharged through a vent at the bottom of the screen behind the hinge. The fan lowers the air pressure inside the case causing outside air is drawn in the case, displacing the hot air inside and helping to cool the other components.
The computer uses passive cooling to remove the residual heat from the processor which comes mostly in the form of radiant heat. Passive cooling is also used to cool the other components of the computer (memory, disk drives, battery etc). Passive cooling works by conductive heat transfer ie. syncing to the case of the computer. Some of the heat then is radiated. Some of it is transferred from the outside of the case via convective cooling; the foot pads on the bottom cover are designed to raise it up just enough to allow air underneath for convection to occur. (Convection is the process in which hot air to rises and is displaced by cooler air.) The rest of the heat from the bottom cover is absorbed by whatever surface you have the computer on.
The processor will not sync to the case very much if the board is assembled properly however the other components of the computer will, requiring the case to be in open air to allow for passive cooling to take place.
If you have some sort of covering such as a plastic snap on case it will likely interfere with passive cooling in all of it's 3 of it forms, this will cause the computer to be abnormally hot. I recently saw someone in the Apple store with a MacBook Air experiencing abnormal heating due to a plastic snap case so this particular problem is not unique to MacBook Pros and it is not the cause of the issue being discussed here. I do not recommend the use or anything that covers the computer while it is running with the exception of something that covers the back of the display panel only. If you are worried about your computer getting damaged go and buy a laptop insurance policy from Worth Ave group. The insurance does not cover cosmetic damage or misplaced items but will cover accidental damage including spills. This insurance also covers theft, vandalism and natural disasters, is quite inexpensive and the claims process and deductible  is similar to most phone insurance plans (which they also offer).
User induced overheating can also occur when the computer is placed on an improper surface such as a couch cushion, car seat, bed, pillow etc. Doing this can interfere with both passive and active cooling.
As I mentioned earlier In all likelihood if your computer was produced after May it is not affected. I personally have been in posession of 3 MacBook Pros, one produced before May which had the problem, one after which had no problems and one produced more recently that has mind blowing thermal performance way beyond all of my expectations.
So the question at this point is exactly what is the problem, how can it be diagnosed and how can it be rectified.
After extensive research and testing I have determined the issue to be related to improper application thermal paste. I involuntarily became involved in this pursuit as a result of the problems I was experiencing and I did not initially come at from an objective viewpoint but rather one of cautious skepticism. I had anticipated before purchasing my computer that there may be a thermal issue. This anticipaion came as a result of reading an article on ifixit.com about the disassembly of the brand new early 2011 MacBook Pro. When the technician performing the disassembly removed the main heat sync he expressed concern about how much much thermal paste was present, expressing that it seemed excessive. This lead the technician to question wether or not it would cause heating problems.
Proper application of thermal paste is critical to the functionality of the active cooling system and when applied improperly will not properly transfer the heat to the heat-sync which in turn gets cooled by the fan. Proper application of thermal paste insures the heat is removed from the case as efficiently as possible. Doing this both reduces the speed at which the fan needs to run in a lot of situations and prevents too much heat from the processor needing to be cooled by passive means. If is is not applied properly it will eventually lead to overheating of the case as well as the other components of the computer. This can cause damage firstly to the computer's battery and can also significantly shorten the life computer. (Or any other kind of electronic device for that matter.)
The problem can be diagnosed by testing the computer using a program called System Load or any other software that will put your computers proscessor use up to its maximum and keep it there indefinitely. Placing full load on your GPU at the same time during the test is also recommended. Keep in mind, if you are using your computer the fan will spin up if needed for additional cooling. You should expect the fan go up to its maximum speed during the test, it is not in of itself an indication of a negative result. Make sure to have the computer plugged in, fully charged and on a proper surface. A desk or other flat surface should be fine. Exceptions would include the top of a refrigerator since it has insulation just underneath the metal exterior or any surface that is heated by any means such as a dryer or other appliance.
(The temps to follow are in ºF)
Run the test for up to 1 hour. If the case of the computer breaks 93 degrees your unit is likely affected. Expect the unit to even possibly reach temps approaching and exceeding 100º, if this happens immediately abort the test. Also look for the processor temp shooting up to around 180 in the first 30 seconds and the fan spinning up right away. Typically on a properly functioning unit the temperature of the case will end up being somewhere in the neighborhood of 88-91º. If this test is preformed in a room with a normal ambient room temperature of about 68 degrees. Even after an hour the case of the computer should not be significantly hot, just warm to the touch. On a normally operating unit the fan will start to kick in within 90 seconds or so and may not reach full speed even after several minuets.
At one point the case of my computer actually reached 95º during normal web browsing.
This is a problem that I have had successfully corrected twice by reapplication of thermal paste. The first time was on a machine produced prior to may and the second was after a logic board was replaced at the repair depot. (I suspect the inventory turnover is lower for boards than whole computers resulting in a board from the initial production run being installed in my computer.)
If you forget everything I just wrote remember this. #1 if you are using your computer hard enough the fan will end up running at high speed at some point. #2 This problem is not in any way related to the design of the MacBook Pro, or its use/application. #3 This mostly not a problem of the CPU being too hot; these Sandy Bridge CPUs are rated for 212ºf and will routinely be in the neighborhood of 200º, this is hotter than other chips but well within design limits. #4 I have done everything in my power to make sure that this problem has been corrected and I have every logical and evidenced based reason to believe it has been resolved in machines produced after may. #5 This is not an Apple acknolidged issue. Technicians will tell you that there is no problem because these higher temps are normal and within operating limits and if they weren't the machine would shut itself off. (This is a bit extreme; just like a lot of other devices such as electronics, toaster ovens and space heaters with thermal overload protection this automatic shutoff is intended to occur when damage or risk of fire is imminent because the device is WAY outside of normal operating paramaters.) They will also not tell you when asked what these limits are, that they know what they are or in some cases that such figures they even exsist.
I stake my personal and professional reputation on the accuracy of my findings, it is my job as a private consultant to help my clients to resolve complicated and expensive issues just like this one.
Bottom line if you are having a problem and Apple won't fix it on warranty don't ditch your machine, just pay to have it done yourself. In most cases you can pay have it done at the Apple store. It will probably cost you less than 100.00, and it will not void your warranty as long as the work is done by Apple certified technician. It will be well worth it; after all in spite of this MacBook Pro's are hands down the best portable computers on the market, with an industry leading warranty and support to back it up. On it's worst day Apple's service and support is better than any computer/ consumer electronics company, even on its best day.
I hope this helps to clarify this issue! I also hope it will help anyone affected to resolve the problem instead of resorting to a refund and settling for something else.

Answer 1

hello all
you can try this:
Go to system preferences > settings > built in display >  see bottom of window.
check "show mirroring options in the menu bar when available". then click "airplay display" > and select your device.
That's what happened to my MBP - 15-inch, Late 2011 model.