Tom,

     The initial report is good and bad. Let me explain. As I said, I got
my Sonnet
Tempo card Thursday morning. I didn't get around to installing it until
Saturday the 27th though. I set aside the entire day to burning some
back-up CD-Rs and preparing the 6400 to have more internal drives.
This was the longest it ever took for me to do an upgrade on my 6400.
Usually all of my upgrades are done in 10-15 minutes from case opening
to closing again. This time it took 5 hours, including two different trips to
the store. One trip to a Sears to get a T10 torx screwdriver and one trip
to Radio Shack to get what I will call a Y-adapter disk drive power cable.
This may have been a mistake. It allowed me to split the power coming out
of the 6400's power supply so that it could go to to the added drive.
It was already split, from the Apple factory, to supply power to the
stock internal EIDE drive and had a cable already there for the 5.25"
upper-drive bay which I had been using for 4 years with a SCSI drive.
It also had the wires split to provide power to the CD-ROM drive,
floppy drive, the lights and everything else in there. At times it has
had the Avid Cinema PCI card installed and a Keyspan USB card too.

     Sonnet has improved a lot since when I first got one of their G3 L2
upgrade cards. At that time I got what amounted to a photocopied cheesy
looking instruction sheet stapled together. This time around, with the
Tempo Card, it looks professional. A real slick covered manual with
real pages and easy to see illustrations.

     I proceeded to remove my 6400's subwoofer assembly (really the
only logical place in a 6400 to consider putting a 3.5" hard drive), since I
never used it anyway and have external speakers and a subwoofer
connected to my 6400. This is what I needed the T10 torx screwdriver
for. They run about $3.99. So, it is not a bank breaker. :-) I removed
the subwoofer and could see 4 years of dust and dirt that had been trapped
under there. I was also amazed at how the design of the subwoofer
seemed to be poor, as it covered quite a few of the holes on the bottom
of the 6400. I figured this would be good to get more ventilation in there
(espcially since I was adding another hard drive). Before purchasing
the Sonnet Tempo card, I already had a 30GB EIDE Maxtor (5400RPM)
in the front drive bay, and a 4.5GB IBM SCSI in the upper-drive bay. My
mission Saturday was to find room for two EIDE drives. The first choice
easy, as I just removed the 4.5GB IBM SCSI drive and put the new 40GB
Maxtor drive on its sled and in the upper bay area. The second drive ended
up on the bottom of the 6400 case in the front area (away from the
power supply and motherboard as much as possible. So, at that point
I had a 40GB EIDE in the upper bay, a 30GB EIDE down in the front bay
(underneath the floppy drive), and a 10GB EIDE on the floor of the case.
Since I couldn't see any safe way to add a fourth drive I left it at that.
I then decided to not go the Slave/Master route. I ran a ribbon cable
off of each connection on the Tempo card. That way each drive could
be a master and not have to adjust jumper settings to be slave on
one or the other. Per the instructions, I knew I'd have to initialize the
drives before they were recognized. I used Apple's Drive Set-up to
do the job. The 40GB was new and had nothing on it anyway. So, that
was not a problem. The older 10GB had stuff on it, but it had long
since been transferred over to the 30GB, and was just sitting on the
shelf. So, I had no heartburn about initializing it either.

     As always, getting the motherboard out and then getting it back in
was/is real easy on the 6400. However, getting it back in with the Tempo
card and the EIDE ATA66 cable was a lot more difficult. I suppose, in
hindsight, that it might have been easier if I had taken the power supply
out first to make as much room as possible for the card and the cable
and my big hands. :-) Looks like I will have to do that now anyway. :-)

     I put everything back together and plugged the tower back in. WOW!! I
now had three internal EIDE hard drives and 80GBs of internal storage.
Better yet, I partitioned and had 5 disks mount on the desktop. Yahoo!!!!
The machine was DAMN quiet. Whoah, all the dust being blown out and
everything, really kept the fan from oscillating so much. Then, out of
the blue, BOOM!!! My 6400 shutdown. I thought maybe I had stupidly
plugged in the wrong power cable and had been running off of my UPS
battery (since it had been about 15-18 minutes before the
sudden shutdown took place - about the maximum amount of up time
my UPS can support before running out of juice and shutting down).
I checked the back of the 6400 tower case and it wasn't plugged
just into the UPS, but the wall as well. So, puzzled, I then checked the
back of the tower case. I hit the power button and rebooted. While it was
rebooting, I placed my hand in the back where the fan should have been
expelling the 6400's hot air and there was no warm air current coming out.
In fact, the case was hot to the touch and so was the metal protruding
from the case. It then occured to me what had happened. My 6400 was
so damn quiet because the fan wasn't running at all. I had invented an
i6400. :-) That is right, a fanless 6400 like a fanless iMac. The problem
is that this 6400 wasn't meant/designed for that. I ran Gauge Pro and
saw my CPU temperature was 99 degrees celsius (over 200 degrees
farenheit). Metronome reported the same reading. I also discovered that
they both maxout at 99 degrees celsius and 218 degrees farenheit.
Ouch!!! My poor 6400 baby was roasting!!! Normally the CPU was
between 57 - 63 degrees celsius. So, this definitely was a/THE problem.
I unplugged and took apart the 6400 again. I checked for a loose cable
connecting something. I found none. I then disconnected the third
drive and just let it run with two again (albeit 2 EIDE instead of
one EIDE and one SCSI drive). Still no fan. So, since about 11:30 last
night, I've had the side and top off of my 6400 and letting it run that
way. I'll call the service company first thing tomorrow morning, as
my extended warranty is good until September 2001, and have them
buy me a new Power Supply. The supply is fine. The fan has just died,
but I may as well get the old 6400 a new power supply, as it is due
for one anyhow. I've found some places on the net that sell them.
Most seem to be backordered. The price has come down though.
Used to be close to $300 for a power suppply. 6400 150 watt
power supplies are now to be found for under $100 at most
places with a trade-in. So, in case the extended warranty contract
won't cover this part, I can still get one. So far this morning my
6400 is running at 87 degree celsius (188 degrees farenheit). I love
the silence, but the longterm heat is not good I'm sure. I don't smell
burning wires or solder though. Also, if it was TOO hot, I'm sure it would
just shutdown like it did before. The thermal circuitry I guess. It hasn't
gotten so hot as to shut itself down like it did when it was all closed up
with the beige plastic. So, since heat is a bigger problem than dust, I
will run without beige plastic panels until the replacement power supply
comes. Later today I will plug the other EIDE drive back into the
system and see if it crashes and shuts down again. If so, then this
6400 can only support the two drives. Be they SCSI or EIDE and my
adding a third drive is what killed the power going to the fan.

     So, the question is did the Tempo card cause this or was it
just a coincidence? The card does what it promises. I had three
EIDE drives installed and running. So, I like it. However, the
lost fan has me concerned. Maybe I did overload the power supply.
Maybe I should have been content with two EIDE internal drives
instead of trying to go for three or more inside. I'll know more as
the week goes on. Wish me luck. Feel free to post this or edit
it down to size for your website. Hopefully it can help others
out there who are contemplating this card and have a 6400.
Also, feel free to ask me any other questions you might have
about this that I didn't answer. 

(later he wrote back that the ribbon cable for the IDE card
was blocking the fan intake. moving the cable fixed the issue-Tom)

     My 6400 is equipped as follows:

OS: 8.6
RAM: 136MBs
Stock 8X CD-ROM drive
30GB EIDE Maxtor
40GB EIDE Maxtor
Stock floppy drive
CommSlot II ethernet card
ATI 3D Plus graphics card
External LaCie SCSI CD burner
External Apple 2.4GB hard drive
External 540MB Nomai removable cartridge drive
Umax 600S SCSI scanner
Sonnet G3 L2 cache upgrade card (300Mhz with 1MB backside cache)
Sonnet Tempo ATA66 PCI Host adapter card
Apple TV/FM card
Epson Stylus 740 printer
Altec Lansing speakers


Rodney