Re: Going to one HD
Date: 08/25/05

Date: 24 Aug 2005 21:01:12 -0700

Jean-David Beyer wrote:
> wrote (in part):

>>(My favored technique is removing the CPU
>>fan, flipping/undervolting the PSU fan, and ducting the PSU exhaust at
>>the CPU.)

>Why would you want to duct the hot PSU exhaust at the CPU?

Mainly because it simplifies duct design. Air blown out of
a duct has some directionality, so it merely has to be
directed toward the heatsink. Air sucked into a duct comes
in equally from all directions, so it needs to be nearly
a perfect fit. Also, heatsinks tend to be more effective
when air is blown downward at it rather than sucked upward
from it.

On two of my workstations, I don't even have a duct! The
air blowing out of the flipped fan PSU is already directional
enough to sufficiently cool the CPU.

>Intel specifically says to be sure the fans pick up cool air from the front
>of the case and not pick up hot air.

For a single fan computer, the CPU and PSU usually have to share
airflow in series, and that means compromises.

It makes more sense to put the PSU before the CPU than
putting the CPU before the PSU. The CPU typically tolerates
higher operating temperatures, and also typically generates
more heat than the PSU. Also, CPUs tend to have built in
hardware to throttle or shut down automatically in case of
overheating. A PSU's thermal safety feature is usually
limited to thermistor fan control, if anything.

For quiet computing, thermistor fan control is a mixed
blessing. If the PSU is sucking hot air from inside the
case, the fan will usually ramp up and ruin quietness at
even modest loads. However, if the fan is flipped so that
the PSU is sucking cool air from outside the case, the
fan will only ramp up under very heavy loads (if ever).

>>>8. Change the plugs on the 200 MB hard drive (hdb) and make it

>>Before you chuck the 20gig drive and move the 200gig drive (surely not
>>200 megs), boot into Linux and modify your /etc/fstab file. You want to
>>replace all references to "hdb" with "hda". Then you can move the drive
>>and fix up GRUB and such.

>Can the O.P.'s BIOS handle a 200 gig hard drive?

Yes. I deduced that it couldn't possibly be a 200meg
drive because there's no sense in discarding a 20gig
drive instead of a 200meg drive.

Isaac Kuo