Don,

I know this would seem obvious, but when you said you touched the CPU and it
was very hot, did you touch the actual CPU or the heatsink?

If there is no heatsink, then that is the problem right off. All processors
today have to have a heatsink. Not since the days of the 286 have heatsinks
not been required.

Is this a heat pipe style heatsink? If so, what part of the heatsink did you
touch that was very hot?

If the CPU itself is hot, but the heatsink or heat pipe block is not, then
there is a problem with the thermal contact between the CPU and heatsink.
Perhaps it got knocked partially off, or the thermal paste/pad is
insufficient or bad. Try removing the heatsink and check that it is
installed properly using new thermal paste making firm contact with the CPU.

If it has a heat pipe style heatsink, and the block that contacts the CPU is
hot, but the fins (usually connected to the block via copper tubes or pipes)
are not, then the heatsink itself has failed. Heat pipe style systems use a
conductive fluid to transfer heat using thermal convection to cause the heat
to travel from the block to the fins. If the fluid leaked out, then it will
no longer work. These types have become more popular of late due to the need
for far more fin area than can be attached directly to the CPU because of
interference with motherboard components or other components in the case.

Russ Poffenberger
[log in to unmask]

-----Original Message-----
From: Personal Computer Hardware discussion List
[mailto:[log in to unmask]] On Behalf Of Don Penlington
Sent: Wednesday, January 07, 2009 7:48 AM
To: [log in to unmask]
Subject: Re: [PCBUILD] CPU overheating at idle


I'm working on a friend's 6-month old computer. It has an Athlon 64-bit 
dual-core 4200 chip and running XP SP3 with 1 Gb RAM.

It has suddenly stopped booting into Windows. As soon as it is past the 
bios stage, it cuts out as if the power has been cut.

I suspected overheating, so I got into Bios and checked temps. The cpu, 
with only bios loaded, is slowly building up to 75c. At that point the 
power cuts out---I guess it's set to do so.

My guess therefore is that as soon as XP starts to load, cpu temperature 
may be increasing within a few seconds to the point where power cuts 
out.  Taking the sides off, the cpu is almost too hot to touch.

If I power off, blow air in via a desk fan, and wait several minutes for 
the system to cool, it will remain in bios for several minutes before 
cutting out. If I immediately try to reboot, it will cut out almost 
immediately. So it looks to me like a cpu overheating problem which is 
causing the boot failure.

What could be causing the cpu to overheat so rapidly?  Faulty power supply? 
It's only 6 months old!

Don Penlington


 From the Beach at Surfers Paradise in sunny Queensland. Computer tutorials,
local scenery,  and other things at my website:
http://users.tpg.com.au/deepend/index1.html

                  Visit our website regularly for FAQs,
               articles, how-to's, tech tips and much more
                          http://freepctech.com

              The NOSPIN Group is now offering Free PC Tech
                     support at our newest website:
                          http://freepctech.com