lol My ol' Core 2 Duo laptop used to overheat... Problem was ASUS thought it would be a good idea to hook up a hot running Core 2 Duo @ 2.6Ghz and a hot running AMD Radeon 4650M card to a single tiny heatsink...
So I cut a big hole out of the cooling intake at the bottom and installed a metal grill
I still use a high-end undercooler and some side fans. The power brick also has ventilation holes drilled in the top
I quite often compile up Gentoo packages for hours on end and the thing doesn't break a sweat now... Plus gaming doesn't lock up the machine anymore
I also use the phc-intel patch which is amazing - it drops >5 watts off my power draw at any CPU load (it works by undervolting your CPU). Not so good for Intel CPUs after the Core 2 Duo though I believe (although it is being worked on for Sandybridge I believe)...
AMD powermanagement in the 3.11 kernel works very well
- so I now use the radeon
OSS kernel driver. If you have dual GPU's (I don't) you probably want to look into hybrid solutions to disable the discrete AMD card when you aren't using it. Would be a nightmare to setup if using the Catalyst driver though I guess.
I use a cpupower
daemon to limit the maximum frequency for my CPU as the ACPI temperature of it rises above setpoints. Effectively this is artificial thermal throttling.
The thermal shutdown temperature for mobile CPU's is often around +100C. They will operate up to this temperature - but not very happily and in my case (with the shared heatsink) the GPU will overheat as well in a kind of "thermal runaway"... GPU and CPU chips age faster when you run them hot or overclock them - wearing out much sooner than they otherwise would.
I guess most of this is less relevant on a modern Haswell-based laptop. I did upgrade a Desktop PC for a friend recently. The low power variant of the Core i5 (@2.6Ghz) was idling at 26C on the stock cooler.
There's also some nice bedroom reading on power management @ TLP