Now that Bitcoin 'Block Erupters' have dropped down to $10 a pop I've grabbed a few and taken a hack at this overclocking mod.

You will need some very reasonable cooling to run a 16mhz oscillator  and your current per stick will jump up to about 1.1A!

The reason these things run the stock 12MHz speed they do became very obvious while I was testing, at full load they draw right about 500mA. They sized the Voltage regulation resistors so that the core sits near the cusp of functionality, but this also means 'stock' Block Erupters are undervoltaged because of this compliance and they actually are having a higher block rejection rates than my overclocked ones.

For the 'R1' resistor I would not suggest going all the way up to "1.5K" like some guides suggest. 1.24K is the lowest you should go at 16MHz though, but 1.3K should work well in most all cases and I'll explain why next.

Another thing I found in testing is that the tolerances on the Voltage regulators are pretty crap, the feedback range Vref in the datasheet is "0.788V-0.8V-0.812V" One of the stock erupters I've left alone for testing reads off 0.8v on the dot and it still has the occasional block failure

so my stated "1.3K" works on ones that are at the low end of the Vref range. 
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