[quote name=\'Beomagi\' post=\'118725\' date=\'May 9 2006, 03:00 PM\']you can overclock from software, using tools like clockgen, riva tuner(videocards) etc. or from the bios
If you have an hp, then while it's possible to find a clockgen that works, your board isn't going to be designed the way an enthusiast board is designed - you'd lack voltage increments, fsb increments, the power phase to the chip wont be as overdone as say, a DFI or ABIT board.
As for decreasing the life - it depends on the manner of the overclock (as J0etann outlined), and the processor.
e.g. The athlon xp-m. These were desktop bartons retested at lower voltages to see if they'd work. You could take one of these and jsut increase the fsb from 266MHz to 400MHz, drop the multiplier to 2/3 it's value, and set the voltage to that of the desktop counterpart, and it would run almost guaranteed. You wont be decreasing the lifetime compared to the other desktop chips because it was designed to handle that voltage, only tested to run with less. after that keep in creasing the multiplier, and you'd get anywhere from 2.3 to 2.7GHz on the old athlon-xp core. Not bad at all for back then
e.g.2 The 2.4C northwood. If a company has as easy time making chips, they wont sell all at just high speed. They'd lose out on either low end if it's too costly, or high end if it's too cheap. So intel for a while underclocked their chips. 2.4C northwood pentium 4s would easily run at 3.0 to 3.2 GHz without any voltage increase. Keep in mind, these chips are TESTED and set; they're designed to run at these speeds. But either one test failed, or they had a glut of high speed chips and had to make up bottom.
e.g.3 The pentium-m/celeron-m on desktop. Intels hottest chip - surprised? There's a difference between power and temperature. The prescott runs at about 60-70C tops (safely) but produces up to 130W. Old pentium-m's were designed to run even at 100C, but produced only 30W. Why was it hotter? It was designed to handle being in a crappy environment - a laptop. Not much cooling. Oh the pentium 4 on your lap can cause burns - because the heat energy given off is sooo much, but the "hot" pentium-m on your lap barely made you sweat. When desktop boards were available, overclockers put desktop heatsinks on these, letting them safely pump voltages through it and overclock them without worry on shortened lifespans.
e.g.4 This is BAD

The newcastle 130nm line doesn't like to be overclocked. The voltage isnt correct but i was still pushing 1.6+ which is scary. Only did that once, but if i had run this chip for a long time, then that would have
burnt up easy 
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Possible slight understatement

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