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 » AMD x86-64 Processors
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Cooling advice URGENTLY sought!!



 
 
Thread Tools Display Modes
  #51  
Old June 22nd 04, 02:59 AM
Ben Pope
external usenet poster
 
Posts: n/a
Default

CBFalconer wrote:
Ben Pope wrote:
General Schvantzkoph wrote:

Power is V^2/R so reducing the core
voltage reduces the power dramatically.


I think that heat production in a chip is more about capacitance
than resistance. The voltage and capacitance (and switching time)
will affect the amount of current that flows, and that will
determine the heat production.


In CMOS logic the action consists of charging and discharging many
small capacitances at the clock rate. The charge q transferred is
proportional to V and C, i.e. dQ = CV. The time interval dT is
inversely proportional to frequence, so the effective current I is
dQ/dT, and the effective power is V*I. Since q is proportional to
V, that gives the usual power vs V squared relationship, but power
is also directly proportional to frequency.

Just keep your eye on the fundamental ball, power is voltage times
current.


I good point well made. Much better than I tried to make it. :-p

Ben
--
A7N8X FAQ: www.ben.pope.name/a7n8x_faq.html
Questions by email will likely be ignored, please use the newsgroups.
I'm not just a number. To many, I'm known as a String...


  #52  
Old June 22nd 04, 09:38 AM
Arnfinn Haraldsen
external usenet poster
 
Posts: n/a
Default

It shold not overheat like this in that case, it has adequate (but barely)
airflow with its two intake fans in front

http://www.modthebox.com/review287_4.shtml

did you remove any plastic protection and put on thermal paste?

maybe you can set a fan at top to get air out, but dont use the fine black
grid - it will reduce the airflow by 75%.


"Miss Perspicacia Tick" wrote in message
...
I have an FX-53 based system on an SK8V board in a CoolerMaster Wave

Master
case. The HSF is a Swiftech MCX64-V with a Delta fan and the PSU is a 480W
Tagan.

The rest of the spec is as follows: -

1GB RAM
3xSATA HDs (2xRaptor in a RAID 0 array plus a WDC)
9800XT 256MB
Audigy 2 Platinum Pro XS
Plextor 708A
Samsung combi


I have a *serious* issue with overheating - and I do mean *SERIOUS*. With
the side panel on, it *IDLES* at between 60-65°C (140-149°F) and once,

when
I was doing nothing more than designing a brochure in Publisher, it hit

70°C
(167°F) and locked up. I have moved all obstructions from around the HSF

and
made sure everything is dust free (it's only a day old!) Is there a fault
somewhere? I was lead to believe that the motherboard had smart

temperature
control - well 60-65 at idle tells me either it doesn't or it isn't

working.
Is there a setting I've overlooked in the BIOS (I didn't build it)? I

don't
have much spare cash to spend on any more cooling (and there isn't any

room
in the case for any more fans anyway!)

I'm running it with the side off at the moment and it's stabilised at 45°C
(113°F) - but I don't want to have to do that forever! I'm hoping for an
idle temperature (with the side on) of around 35-45°C (95-113°F) and

50-55°C
(122-131°F) under load. Achievable? I don't think it's asking *too* much,

do
you?!

I've RTFM and it's not exactly explicit!

How do I achieve what I consider to be the optimum running temperature?! I
will call the bloke who built it on Monday, but I thought I'd ask here
first - I know that MBM isn't known for its accuracy but, on this

occasion,
it's spot on (I've checked it with the BIOS).

Can someone offer me some cooling solutions that won't empty my bank
account?!

Thanks




  #53  
Old June 22nd 04, 01:05 PM
Miss Perspicacia Tick
external usenet poster
 
Posts: n/a
Default

General Schvantzkoph wrote:
On Mon, 21 Jun 2004 20:54:31 +0100, wrote:


"Ben Pope" wrote in message
...
General Schvantzkoph wrote:
Power is V^2/R so reducing the core
voltage reduces the power dramatically.

I think that heat production in a chip is more about capacitance
than resistance. The voltage and capacitance (and switching time)
will affect the amount of current that flows, and that will
determine the heat production.

Ben


Capacitive Reactance (Xc)
If you had a pure Capacitive circut then the P = V^2/(Xc) might be
correct Of course, it's a ton more complicated than this in a
processor..
and I would have to wonder just how much total capacitance there is
in a processor (I wouldnt guess it's a lot given it's size)
;P


The leakage current is the resistive part, the capactance is
reactive. The capactive part dominated in earlier generations but as
line widths have become smaller the leakage has become much more
significant. In both cases the power is related to the square of the
core voltage. The reactive part is linearly related to the frequency,
so reducing the clock frequency reduces the reactive power. If you
lower the clock frequency and lower the core voltage you get a very
large reduction in power.


I wish I'd paid more attention in Physics!



 




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
Cooling advice URGENTLY sought!! Miss Perspicacia Tick General 50 June 22nd 04 01:05 PM
Converting RAID 0 array to RAID 0+1 - Advice sought. Mod General 0 December 1st 03 04:40 PM
Need URGENT cooling advice!! I'm too scared to do anything much! Perdita X. Dream General 11 October 25th 03 04:49 AM
Advice please on hardware cooling mcr General 1 September 11th 03 04:48 PM
Dell Dimension XPS T450 - Upgrade advice sought. Mod General 1 July 7th 03 10:42 PM


All times are GMT +1. The time now is 08:12 AM.


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