How Do I Overclock Core 2 Duo 2 GHz Gateway DG965OT?

You need an overclockable motherboard the intel boards aren't supposed to be overclocked, best bet if you want more power but not new board by a new cpu, or just get another board. I have a gateway and the pcs are pretty good anyway best thing if you have that motherboard as i do you need new graphics card more than a cpu.

  It is my experience that most mass marketed computers
cannot be over clocked especially (Gateways, Dells, Compaq's, and HPs), if you
want such an ability you need to either custom build your system or go with a
company that specializes in building "Gaming Systems" such as alien ware,
as an example, as over clocking is a feature gamers and computer enthusiast
value in their systems. There are two ways to over clock, the multiplier or the
FSB (Front Side Bus), one is CPU dependent (multiplier) and the second is
mother board dependent (FSB), the ability to increase the multiplier is mainly
found on Intel "Extreme" chips where the multiplier is unlocked
allowing for the incremental increase in the processors speed. Since most of us
are unable to afford an extreme chip we usually use the FSB as a means to
incrementally increase the speed of the processor, both require a motherboard
that allows access to these features. You will also need extra power plus the
means to increase cooling for the CPU/system as there WILL be an increase in
heat generation.