Posted by Hans-Joachim Zierke on June 17, 2009, 8:15 am
 


I want to use an Athlon XP 1500+ for a 24/7 system. Unfortunately, the CPU
needlessly doubles as a room heater.

So my idea is, to underclock from 1333 to 1064 (or some similar figure). Now
the question: How do I calculate VCore for the lower frequency?
1333 -> 1064
1.75 -> 1.??


Hans-Joachim





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Posted by Wes Newell on June 17, 2009, 11:48 am
 

On Wed, 17 Jun 2009 12:15:49 +0000, Hans-Joachim Zierke wrote:


Pretty much trial and error. However, if the default is 1.75, then you've
got an old Palomino core cpu that runs very hot compared to the newer
Tbred B cores. Look for a cpu with cpu id 781 (Tbred B core). I've run
them fanless at low speeds with voltage as low 1.3v iirc.




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Posted by Hans-Joachim Zierke on June 17, 2009, 2:37 pm
 


Wes Newell schrieb:



   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^



Yeah, I know, see above. Good reason for underclocking. I thought that
with 20% MHz less, even a Palomino should behave. Wrong? I could go to
900 without performance problems.




Tried it, but got offered Palominos only, around here. Most Athlon
XPs might already have seen the trash bin.



Hans-Joachim



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Posted by Wes Newell on June 17, 2009, 3:29 pm
 

On Wed, 17 Jun 2009 18:37:34 +0000, Hans-Joachim Zierke wrote:


Well, you can certainly lower the speed and vcore and it will help. I
would think you couold probably lower the voltage to at least 1.5v and
still get it to run reliably at 1Ghz. That should lower the temps
considerably. But like I said, about all you can do is experiment with it
and see how low you can get it.

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