A computer components & hardware forum. HardwareBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » HardwareBanter forum » Processors » General
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Processor heat dissipation, Leakage current, voltages & clockspeed



 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #1  
Old October 24th 04, 08:16 AM
The little lost angel
external usenet poster
 
Posts: n/a
Default Processor heat dissipation, Leakage current, voltages & clockspeed

I know I'm a bit slow to start looking up this since the Prescott
thrust the issue into lime light. I didn't quite follow the major
discussion some weeks back. My friend got himself a spanking new
Prescott and claims it wasn't that hot despite claims. Yet Intel did
cancel the 4Ghz version so it got me thinking again whether the heat
increases dramatically with clockspeed. Since leakage was the big
thing thrown about, whether that was what increased with clockspeed.
And whether we could do any experiments to test it out.

So I started doing some reading up mainly from the tutorial document
posted some time back. Tried to understand these issues but don't
think I got very far. Would appreciate it greatly if the resident
experts here point out where I might have understood it wrongly.

I don't understand most of the explanations for how these are
calculated (most of the documents assume proficiency with mathematical
symbology which every regular visitor here knows by now I suck at
PPpP). So here's my best effort at arriving at something useful to
me as a layperson who's interested only in getting a useful real world
approximation of how these things are, say x.x rather than x.xxxxxx
kind of accuracy PpP

Reading, googling and all that, I get formulas and statement that
generally say that

Total Power = Dynamic Power + Static + Leakage + Short Circuit

Dynamic power is directly related to clockspeed. Leakage doesn't care
about clockspeed and is a function of the process/technology but
appears to be in direct relation with temperature, i.e. hotter
processors will leak even more power?.

I got a bit confused with a graph that displaying Leakage current vs
Vgs. http://www.cse.psu.edu/~vijay/iscatu...al-sources.pdf
at pg 7. It seems to imply that lowering voltages will increase the
leakage??

Anyway, the point is, can I say that given the usual x86 processor.
The difference between the power dissipated at 3Ghz and at 4Ghz is
still mostly clockspeed.

Because dynamic power has to do with whether there's any actual
activity, both a 3Ghz and 4Ghz would have similar power draw when
idling since leakage will be there but dynamic would be very low.
While Static and Short are pretty much constant? Or would Short also
be directly related to the amount of activity since it's determined by
the slope of the signal so if there's no activity, there's no direct
current situation since there's no switching done.

So if we set the same (static becomes a constant) prescott at various
vcore (changes leakage right?), change the clockspeeds (changes
Dynamic), measure idle and load power dissipation, would we then be
able to calculate roughly the power used by Dynamic, Static, Short and
Leakage?

TiA!!!!

--
L.Angel: I'm looking for web design work.
If you need basic to med complexity webpages at affordable rates, email me
Standard HTML, SHTML, MySQL + PHP or ASP, Javascript.
If you really want, FrontPage & DreamWeaver too.
But keep in mind you pay extra bandwidth for their bloated code
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Advice Please: The Importance of Hard Drive RPMs Darren Harris Homebuilt PC's 95 August 24th 04 11:16 PM
Changing 'default' FSB speed with Tualatin? ~misfit~ Overclocking 71 August 4th 04 07:26 AM
Are mains surge protectors needed in the UK? Bagpuss General 259 July 20th 04 08:19 PM
Are mains surge protectors needed in the UK? John McGaw Homebuilt PC's 177 July 20th 04 08:19 PM
my new mobo o/c's great rockerrock Overclocking AMD Processors 9 June 30th 04 08:17 PM


All times are GMT +1. The time now is 03:38 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 HardwareBanter.
The comments are property of their posters.