The installation went fine, but there are 3 issues.

1. The cooler is attached by screwing 4 nuts over the cooler's 4 nipples close to the GPU. One has to take care to fasten the 4 screws evenly, half a turn each, then going to the next. Otherwise one could easily damage the unprotected GPU.

2. The fan's power connector doesn't fit into the card's connector. I had a spare cable with a matching connector, so I cut the fan's cable and attached it to the spare cable.

3. The regular fixing nuts are very large. Luckily, there are smaller fixing nuts for SLI included. I used these (see picture), and the card just barely fits into the Mac Pro.

The card is practically silent even while playing games, plus the max temp dropped from about 90°C to about 80°C.
Cheers, Oliver

Other X1900/VF-1000 User Comments:

(added 1/30/2008)
"I just finished installing a Zalman VF1000 cooler onto the X1900 card in my Mac Pro tower (original model). I'd add just a couple comments...
First, the fit is REALLY tight.. Even the little screws were almost too much to fit the card in it's usual slot. I actually had to reach over the card and push it down slightly in the back to make it slide back into the PCIe slot.. But it's in there, & working fine. I may cut down the thumbscrews, as mentioned in this page:
www.xlr8yourmac.com/Graphics/9800_VF900_cooler_install/VF900_install_on_mac_9800.html
But even then, it still doesn't look like you'd gain any space under the card. Might be worse off...

Second, I did plug the wiring from the Zalman fan right onto the ATi card, and it works just like the old fan did - that is, the card adjusts the Zalman fan RPM depending on whatever programming is on the card. However, I did have to do 2 things.

The plugs are not the same shape - that is, you can't plug the Zalman plug onto the ATi plug since they're different shapes. However, it was easy to physically remove the plug socket on the card using a needle-nosed pliers - just grasp it and gently rock it back & forth as you lift on it, and it will slide off the pins, no harm done. I stuck it onto the old fan's wiring for safe keeping.

And, the wires are in the wrong order on the Zalman plug. If you look at the stock ATi fan, the 3 wires are white-black-red (starting closest to the fan outlet side, or the back of the computer), but on the Zalman, they're white-red-black. So you have to switch the positions of the red & black leads. So, if you carefully press into the middle slot on the Zalman plug and simultaneously pull on the middle wire, you'll release the wire from the plug. Do the same to both red & black wires, then insert them back into the plug so you have white-black-red. The pins on the ATi card and the spacing on the Zalman plug are the same, thank you very much.. Plug 'em together & you're golden.

It was gratifying to listen to the new Zalman fan upon first boot after installation. The old fan.. Let's just say it sounded like a mini turbine or dentist's drill when it's running full bore (which happens briefly twice during the boot process). The Zalman was audible with the side open, but as a quiet whoosh, during the two times when the fan normally spins up during booting.

After playing Ambrosia Software's Redline with the old fan, it'd be spooling up to that annoying dentist's drill pitch.. The Zalman is blessedly, gratifyingly quiet. By the way, Redline is a killer driving sim - IF you have a Logitech Momo steering wheel/pedal controller or other analog controller (the Momo has force-feedback, too, which is WAY cool). Oh, and don 't be a wussy & play "arcade" mode - it's simulation or strict modes or nothing!

Oh, and while I never apparently had any overheating (except the evidence of the high RPMs of the cooler fan), I was poleaxed to see how much dust was clogging those fins in the old cooler! Compared to the pics on this page, mine was even worse:
www.xlr8yourmac.com/Graphics/radeon_X1900XT/X1900XT_dust_buildup.html
I'm sure I could have helped lower the RPMs of the old fan some by cleaning it out, but MUCH happier with the Zalman.
Cheers, Andrew"

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