Topic: Mac Mini Overclockable? This guy seems to say it is

[Monty]

Found this story off the inquirer:

http://dialspace.dial.pipex.com/prod/dialspace/town/pipexdsl/q/aqza37/macmini/index.html

[Bonk]

I'll never understand overclocking... someone paid a bunch of engineers a lot of money to determine the operating conditions and cooling requirments of a particular IC. He's sure there's no heat issues? Particularly in such a small box (like laptops built to self-destruct with heat).

Why not just buy a better processor rather than burn out a cheap one faster? I'll never understand the consumer mindset that cheaper is better no matter what... and people fail to see how they can be fooled with numbers that look the same...

 

[Nemesis]

Though not an overclocker myself I do know a bit about it.

When a CPU is manufactured it is tested to see if it has flaws.  Then it is tested for speed.  They test to the highest speed that they need.  For example once Intel has enough 3.6ghz chips for current sales they don't test the remaining chips to that speed, just to the next highest speed that they still need.  All the chips are made to the same specifications on the same production lines.  When the manufacturing procedure is mature most of the chips can operate at or near the highest speed that  any of the chips are rated for.  Most are just marked at a lower speed for marketing purposes. 

In many cases you can take a $75-$100 chip and have it perform like a $750-$1000 chip.  The cost savings are enormous, even if you burned 2-3 chips to find one that worked you would still be well ahead on cash.  If you know what you are doing you can do so safely and gain much enhanced performance without burning out the chip.

On a similar note the overclocking people would use chips that were not rated for multiprocessor systems in dual processor machines.  The price differential between a Celeron and a Xeon of the same speed is very high, the performance difference is much less.   

For example I am typing this on a dual CPU Athlon 2400XP.  The XP is not rated for dual processor mode.  It had a circuit on the surface of the chip broken by a laser to disable that function.  Restore the circuit and the chip is almost certain to function identically with the Athlon MP for 1/3 the price (at the time I did it).  Even now that both chips are at the end of their lives the XP is l $110 and the MP is $180.

Of course once the vendor believes enough chips are being used in ways they didn't intend they begin to block that usage by minor modifications to the chip.  Most of the modifications are made after the chip is manufactured.

[Bonk]

Ah, thank you Nemesis, that explains much of it to me... I was aware of such lot/batch differences in ICs and manufacturer labelling - I just never put it together with why one might overclock.  I can relate, being a tinkerer myself.  Another product that gets marked as two lines or more depending on test results on products off the same line is chromatography columns, same product - different price depending on testing. Columns labelled as lower grade may in fact be as good as the high grade ones if testing was not continued once quotas on the high grade product were met...

[Nemesis]

You are quite welcome Bonk.

In a similar vein way back in the days of the 5.25" floppy disk I bought hundreds of Nashua single sided floppies and used them as dual sided.  I had found out that they were Dysan dual sided disks that had either a/ failed the test for the 2nd side or b/ had not had the 2nd side tested due to being over the volume of dual sided Dysan brand needed.  Less than 1% failed to function as dual sided and I never had a data loss.  The Dysan brand of dual sided floppies was 10x the price.