I ran in to a similar case (a stubborn person with P-II 400 and tons of
cards in mid-tower case).  I did the following and the system is running
fine and heat measurements look pretty good:

1) tack welded (MIG) additional baffles into case to direct airflow to each
component.
2) added fan to air inlet
3) added fan to air outlet
4) mounted heat sinks on the hottest chips (i.e. AGP video chip)
5) used baffles to route power supply, hard drives, and CDROMs onto separate
air channel (P/S had its own cooling fan).

With all of this messing around it was about the same price as a new case.
I only took this project because the furniture for this system would not
accommodate a full case (well, and I had spare finned and sheet metal to
move out, too).

Bottom line:  Get the full tower case with extra fan.
Martin Kurr
email [log in to unmask]
> From:         Jun Qian[SMTP:[log in to unmask]]
> Subject:      Re: [PCBUILD] PIII processors
> A client has a PIII computer with 7 cards pluged in (1 AGP, 5 PCI, 1 ISA,
> so
> he used all space on the mobo), also he has CD-ROM and CD-R next to each
> other
> ('cos the case has 3 5" bay, but the lowest one is unusable because the
> size
> of Abit mobo), 2 harddisks in a normal size ATX tower case. Now he's
> runnig
> the computer w/o case and use a fan to blow ait to the computer. That was
> the
> only idea I could give him to run the computer without overheat and change
> to
> a fulltower case. (one thing I don't understand is he knew the danger of
> overheat, but still refuse to use a bigger case and put these much things
> in.)
> Could you tell me how to run this computer with case on? I ran out of idea
> how
> to make the way. Many thanks!
> J Qian
> PS: last summer, the only way to run my own computer in home (without
> overheat
> problem)  was to left the case on (at that time, I didn't have an extra
> fan
> for the case). I personaly disagree with the "case off will rise up temp"
> issue.

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