Does a Pentium 3 800MHz need a fan?

It puts out a LOT of heat. If you don't want to fry it, get a fan.

--
DaveW



Nittaku wrote in message
.be...
...or is passive cooling enough. I want to reuse my old motherboard for
something else, but it can't make a lot of noise...

Nittaku wrote:

...or is passive cooling enough. I want to reuse my old motherboard for
something else, but it can't make a lot of noise...


=MAYBE= if you unclock/undervolt it a bunch?
--

Stacey

On Thu, 6 Nov 2003 01:09:37 +0100, Nittaku wrote:

...or is passive cooling enough. I want to reuse my old motherboard for
something else, but it can't make a lot of noise...


As Stacey mentioned, you might consider underclocking, undervolting
it. Running on a 66MHz FSB, 533MHz CPU speed, it might run stable at
around 1.4-1.5V, wouldn't need a fan on the heatsink then though you'd
still need normal case airflow, assuming the typical motherboard with
socket more-or-less right under the power supply air intake (that is,
you should use a power supply with this air intake on the underside.

You don't really need to go to that much trouble though, a P3 800 is
not very hot running, relatively speaking. Intel's datasheets would
give a max wattage but it's in the ballpark of 22W of heat under a
fairly high load situation, but a lot lower if mostly sitting idle on
a motherboard and OS that's ACPI supportive. All but the smallest or
cheapest of heatsinks should be OK with a low-RPM, quiet fan on them.

You might just be able to take the easy way out, get a power supply
fan adapter and run the current fan at 5-7V.


Dave

kony wrote:


You don't really need to go to that much trouble though, a P3 800 is
not very hot running, relatively speaking. Intel's datasheets would
give a max wattage but it's in the ballpark of 22W of heat under a
fairly high load situation, but a lot lower if mostly sitting idle on
a motherboard and OS that's ACPI supportive. All but the smallest or
cheapest of heatsinks should be OK with a low-RPM, quiet fan on them.




It's been a while since I looked at one of those but would a HS off an
athlon fit? If so a HS off a later model AMD with a power supply that blows
across the CPU (some have the fan on the inside that does this) would
probably be plenty even at 800Mhz.

--

Stacey

On Thu, 6 Nov 2003 01:09:37 +0100, Nittaku wrote:

...or is passive cooling enough. I want to reuse my old motherboard for
something else, but it can't make a lot of noise...

IMHO it does with ordinary size HSs; but you can try putting it to 7V
or even to 5V, but not less; at this last you will not hear it at all
.... se my site under electronics ...


-- Regards, SPAJKY
& visit site - http://www.spajky.vze.com
Celly-III OC-ed,"Tualatin on BX-Slot1-MoBo!"
E-mail AntiSpam: remove ##

On Thu, 06 Nov 2003 00:33:14 -0500, stacey wrote:

It's been a while since I looked at one of those but would a HS off an
athlon fit? If so a HS off a later model AMD with a power supply that blows
across the CPU (some have the fan on the inside that does this) would
probably be plenty even at 800Mhz.

Yes, a socket A 'sink would work so long as the motherboard didn't
have capacitors too close to the socket for the paritcular 'sink
used... socket 370 didn't have as large a "keep-out" zone around the
socket.

As with modern systems, people were really anal during the P3 era,
about keeping CPU temps low, even though it was much easer to do with
a Coppermine P3. Even the retail P3 'sink should be enough with it's
fan undervolted to 7V, in all but the worst chassis and ambient
environments. I had a Celeron 733 project that was passively cooled
with a big old passive 'sink from a Compaq Pentium 1 box, though those
were pretty unique 'sinks, twice as long as the socket they'd only fit
on certain motherboards, but I had it on a slotket.


Dave

Nittaku wrote in message
.be...
...or is passive cooling enough. I want to reuse my old motherboard for
something else, but it can't make a lot of noise...


it definately needs a fan

what i sometimes do is get rid of the hi-rpm and noisy cpu fan
then mount a case fan in such a way as to blow down directly on the cpu
heat sink

the larger fan spins at a lower rpm so is quieter
and due to it;s size...actually cools better!

kony wrote:
On Thu, 06 Nov 2003 00:33:14 -0500, stacey wrote:

It's been a while since I looked at one of those but would a HS off
an athlon fit? If so a HS off a later model AMD with a power supply
that blows across the CPU (some have the fan on the inside that does
this) would probably be plenty even at 800Mhz.

Yes, a socket A 'sink would work so long as the motherboard didn't
have capacitors too close to the socket for the paritcular 'sink
used... socket 370 didn't have as large a "keep-out" zone around the
socket.

As with modern systems, people were really anal during the P3 era,
about keeping CPU temps low, even though it was much easer to do with
a Coppermine P3. Even the retail P3 'sink should be enough with it's
fan undervolted to 7V, in all but the worst chassis and ambient
environments. I had a Celeron 733 project that was passively cooled
with a big old passive 'sink from a Compaq Pentium 1 box, though those
were pretty unique 'sinks, twice as long as the socket they'd only fit
on certain motherboards, but I had it on a slotket.

LOL, I've got one of those 'sinks in my drawer, along with a really tall
'passive' 'sink from a Dell socket 7. That one is stepped so it fit around
the PSU, about 5" high on the high side. Must clean that drawer out one day.
--
~misfit~

philo wrote:
Nittaku wrote in message
.be...
...or is passive cooling enough. I want to reuse my old motherboard
for something else, but it can't make a lot of noise...


it definately needs a fan

what i sometimes do is get rid of the hi-rpm and noisy cpu fan
then mount a case fan in such a way as to blow down directly on the
cpu heat sink

the larger fan spins at a lower rpm so is quieter
and due to it;s size...actually cools better!

....and you can duct it with a home-made duct and even a home-made shroud,
maybe pull/push the air through the fins laterally (works really well).
Cardboard is fine for this. I'm thinking of doing it on my Athlon XP.
--
~misfit~