Cheap, and just bursting with overclockability (My 800 is running 1 gig perfectly stable and not too hot. Unf Unf Unf
Wanna overclock that shiny new Duron? Here's how to unlock the multiplier:
Pull your chip out of your motherboard, if it's in there right now. Clean all the thermal grease (you did use that, didn't you?) off the chip. Sharpen a soft pencil -- #2 or less, and mechanical pencils don't work as well as normal wood pencils. And I'm really serious about sharpening it. You want as fine a point as you can put on the lead.
Now, orient the chip so the AMD symbol is right-side-up. There should be a raised metallic box in the center of the chip (about 1cm * .75 cm), with a row of 5 small rectangles above and below it. On the right side, there are 3 more little rectangles. To the right of those, there's some very small dots, lines, and writing. Rotate the chip 90 degrees counterclockwise so the writing is right side up. Here's as close an image of that as I can make in ASCII, copied from a duron 750. Your chip may be slightly different when it comes to lines vs. dots:
L1 . : : : : . | | L2
L3 * : | | : * | : : | L4
Okay. Each colon is called a bridge. What you want to do is connect each pair of the four L1 bridges -- turn each of the four colons to the right of the L1 label into a pipe. Don't get any lead that connects two sets of bridges. That's bad. If you do, you lose your chip when you power it up. So get a magnifying glass if you can't see them, and triple check
that there's no lead connecting the sets of bridges. However, you do want a solid connection, so put a lot of lead over the bridge.
That's it. Plug it in, slap a quality heatsink on it, boot it up and start playing with the multiplier setting in your BIOS (or, horrors, fiddling with jumpers if you've got a stone age mobo). No soldering or tape like in the old celerons. Just a pencil. Some hardcore overclockers insist on using car defroster repair kits, which is essentially metal made to go on liquid-like and dry permanent. Certainly seems more reliable...but you can't use an eraser if you fsck up.
Oh, and a picture in this case is worth...well, a whole lot of words. Do a search for duron multiplier unlocking and check out some pictures of what you'll be doing.