Re: [Sheflug] Today's virtual meeting:-)

[Matthew Collins <nospam [at] janes.demon.co.uk>]

On Sat, Jul 07, 2001 at 02:48:22PM +0100, Guennadi Liakhovetski wrote:
> Hi guys over there in Stoddart Bld. (and everybody else) May we extend
> your meeting with those wishing to be virtually present there (like
> myself)?:-)
> 
> Anyway, next question from me - how bad is underclocking? I've got a
> computer, whose mobo supports P133 maximum, but somebody lended me a
> P166MMX... so, I put it there setting jumpers to 133MHz (I had P75 there
> before). How bad is it for the CPU, mobo, performance?... Am I getting
> a better / worse performance than if I had a P133 there?
> 
> Cheers
> Guennadi

I'm not there either, but I'll try and give you a reasonable answer.
Underclocking is not bad, but the MMX cpus require a different voltage to
the non-MMX pentiums. The MMX (I think the 166 was the first MMX) require
two different voltages, might be 2.8V and 3.3V, but don't quote me on that.
I don't think it will work unless your mobo has got the required support. Or
it might work for a while, but run very hot and then emit magic blue smoke.
As to the performance. Some applications were written to take advantage of
the MMX extensions, but they tend to be games. There are not that many of
them, and you won't see a big difference running the 166MMX at 133. It will
be faster than the P75 you had in there before. You might damage the CPU if
you don't set the voltage up correctly. Check your mobo manual, or
silkscreen. If it says MMX on it, then you should be ok.

-- 
Matthew Collins

---------------------------------------------------------------------
Sheffield Linux User's Group - http://www.sheflug.co.uk
To unsubscribe from this list send mail to
- <sheflug-request [at] vuw.ac.nz> - with the word 
 "unsubscribe" in the body of the message. 

  GNU the choice of a complete generation.