Re: Real time?

[Jon Elson <jmelson-at-artsci.wustl.edu>]

Scott Stephens wrote:

> Intel has an app note (IIRC pertaining to their evil I740 video chip) about
> airflow paths inside of PC
> s and cooling cards. I've lost power supplies because cheap bearingless fans
> failed. You would need extra large heat sinks for a few parts (just pop the
> top and feel the hot ones;

This is a very dangerous suggestion!  There is 400 V DC in these power
supplies!  That can definitely kill you!  The capacitor bank can stay charged
to some significant voltage for several minutes.

> if its too hot to hold its too hot & many vendors
> have app notes on how to calculate heat sinks and air flow for their power
> semi's) and probably need to drill new holes or re-orient the supply to set
> up a vertical convection flow.
>
> >ps
> >totaly off topic but I'm trying to put together a "silent" diskless
> >workstation
> >does anyone know of a way to make an AT compatable power supply
> >work with the fan disconnected (and with extra large heatsinks )

Well, it is possible to make the power supply fanless, and silent, but
there are so many hot spots on the motherboard that it is not going
to be easy to make that run without airflow.  Many, if not most, new
VGA cards need airflow to prevent overheating.  My Pentium computer
will crash unless I have an extra fan bringing cool air to the area
of the CPU.  Apparently the CPU fan just keeps recirculating the same
hot air without some help to drive the hot air away.  (I just put together
a high end system for someone, and it had an Elsa Gloria 3D
graphics card that ran so hot you couldn't touch the memory chips.
These chips were running about 70 C!

Jon