Motherboard shopping

[Tom Metro]

markw at mohawksoft.com wrote:
>> Making sure all the supply
>> voltages are within 10%, or preferably 5%, of their ratings is a good
>> check...
> 
> Hell no!! +- 1% MAX!!! Any more than that will cause problems.

I thought I might have been out in left field with the 10% figure, but I
was too lazy to check. However I knew 1% was also far too precise for a
regular PC power supply. Take a look at the specs on a typical supply:

http://www.antec.com/specs/SP350_spe.html

It's rated +/- 5%.

1% would be an expensive lab supply.


> The 3.5V has to be 3.5v. The 5V HAS to be 5V. The +-12 can be off a bit.

Even their top-of-the-line models:

http://www.antec.com/specs/TPII550_spe.html
http://www.antec.com/specs/Neo480_spe.html

only provide +/- 3%.

Though those are maximums, so under typical conditions you might observe
the supply staying within 1%.

These days the point is somewhat moot, as the precise voltage needed by
the CPU, and probably RAM too, is generated by the regulator on the
motherboard.


This thread has probably gone beyond most readers level of interest, so
I'll take replies off list.

  -Tom

-- 
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
Professional Profile: http://tmetro.venturelogic.com/