Intel's "3rd generation" CPUs, codenamed "Ivy Bridge", bring a number of improvements over the previous generation, Sandy Bridge. Unfortunately, for those of us used to getting progressively faster and cooler performing CPUs from Intel, Ivy Bridge delivered on the former front, but not so much the latter.
The primary culprit (other than the modified design) is Intel's "Turbo Boost" technology, which is just a fancy name for dynamic overclocking. Luckily, by giving Turbo Boost a tighter leash, you can enjoy the benefits of the extra performance headroom, without sending your notebook's temperatures into "surface of the sun" territory.
Below you'll find three options of increasing difficulty and effectiveness, with the third tweak my preference. Be warned, it requires the use of a third-party tool called ThrottleStop that, if used incorrectly, could damage your CPU. But we'll be focusing on reducing temperatures, not increasing them (via overclocking) so the risks are negligible.
3. Reduce The Maximum Processor Speed Via Power Options
This is the easiest, but also the least optimal tweak you can make. Navigate to the Power Options dialog, either by selecting it in the Control Panel, or right-clicking on the battery icon in the notification area and selecting "Power Options". You'll then want to adjust the advanced options for your current power plan and locate the "Processor power management" node.
Now, you have two options: reduce the maximum percentages for "plugged-in" and "on battery" by a large amount, say 25 per cent, or by one per cent to disable Intel's Turbo Boost feature (though this doesn't work on all systems). Essentially you're putting a clamp on how fast the CPU can run, which, naturally, is going to bring temperatures down, but it comes at the cost of performance. We can do better.
2. Disable Turbo Boost Using ThrottleStop
Head on over to TechInferno and be sure to grab version 5.00 of ThrottleStop -- the download link is on the front page, just below the massive header image. Install the application somewhere convenient and take note of the executable's location -- we'll need this information later.
Now, fire up ThrottleStop and look for the "Set Multiplier" checkbox. Don't click it, just look to the right of it for the up/down arrows next to the text box with a number in it (it'll be in the format of "16.0", though the number itself will vary depending on your CPU). Click the up arrow until it says "Turbo". At this point, the "Disable Turbo" checkbox a bit below "Set Multiplier" will become active, allowing you to enable it.
This will stop Turbo Boost from firing at all, but lets the CPU ramp up to its natural maximum speed -- something not guaranteed by manipulating Windows' in-built power options. This dropped the temperatures on my notebook, a ASUS UX32VD i7, by about 10 degrees Celsius, but (understandably) had a noticeable negative impact on high-performance tasks, such as gaming.
Good thing the third tweak provides a compromise between lower temperatures and speed.
1. Tweak The Thermal Power Limits Using ThrottleStop
If you've checked "Disable Turbo", uncheck it. Now, look for a button along the bottom of ThrottleStop's interface that reads "TPL". Click it and a new dialog will open (see right). If you're running a mobile Ivy Bridge chip, the only options you'll want to change are the numbers in the very top boxes. These determine (with a slight margin of error) the thermal limits (in watts) the CPU must obey before reducing its voltage and speed. Change both these numbers to between 10-15, though feel free to go higher or lower, depending on your CPU and your notebook's ability to cool itself. A good rule of thumb is to keep a note of the default values and be sure to stay below them.
Now, when you fire up a demanding program, it'll still be able to use Turbo Boost, but it'll cut out if the CPU exceeds these thermal values. The benefit of tweaking these limits is that they're based on temperature, not voltage or speed, so it takes into account heat produced by nearby components, such as the GPU.
The last option was the best for me -- games and other high-performance tasks performed slower, but the speed difference between shutting off Turbo Boost completely and just applying some more sane thermal limits was night and day. Both resulted in a ~10 degree Celsius temperature drop, but the latter allowed the CPU to ramp up its speed if necessary, while also utilising the Turbo Boost multipliers.
Note: Only apply one of the above three tweaks, especially the ThrottleStop ones.
The last step is to apply the ThrottleStop tweak permanently. Open up Task Scheduler and create a new task. Make the trigger for when the primary user logs on and the action to run the ThrottleStop executable (the location of which you noted down earlier). The task should be run with the highest privileges. Save the task and it'll be run whenever you restart.