Overclocking isn't just limited by heat dissipation, and dealing with the additional heat generation is one of the easier issues to overcome. Much more limiting is the fact that the electronic components in the hardware (everything from RAM to the more "integrated" components on the PCBs) have certain amounts of time which they need to take in order to tie voltages high or low, to either read or output a bit. This amount of time is typically very small as compared to the amount of time that a voltage stays tied high or low, and so isn't a problem, but while you can shorten the amount of time that a voltage needs to stay high or low when overclocking, generally the transition time isn't as negotiable. Increasing clock speeds to the point where these transition times dominate means you're going to get garbage reads and garbage writes out of a component.
This is part of why if you're overclocking your computer, you end up experiencing errors or unexpected crashes even when temperature doesn't go too high. Past reasonable tolerances, you can't just cool it more and expect it to work.
This is part of why if you're overclocking your computer, you end up experiencing errors or unexpected crashes even when temperature doesn't go too high. Past reasonable tolerances, you can't just cool it more and expect it to work.