Having got used to high end graphics cards on the Macs at work, I started putting reasonable bids on various AGP x8 graphics cards for use in my home Dual 2Ghz G5, when they came up on ebay. I eventually won an ATI 9800 Pro Mac Special Edition with 256MB RAM (http://ati.amd.com/products/radeon9800/radeon9800proseme/index.html). However the noise the standard fan made, a high pitched whine, was impossible to put up with. This fan gets my vote as the most annoyingly noisy cooling fan ever mounted on a production graphics card!
My PC expert brother recommended a Zalman replacement unit, and after some research on the web I went for the VF900-CU model. (it's been a popular choice with other Mac cards also...) In "quiet" mode (5V) it is inaudible even with your head in the case and at this setting it still cools better that some aftermarket units at full speed (12V). Full details at http://www.zalman.co.kr/eng/product/view.asp?idx=192&code=013
Problem 1:
The VF900-CU comes with the "Fan Mate 2" fan speed controller, the wiring for which was designed for a PC and needs to be modified for use in a Mac. The power input lead has 3 wires, the obvious red and black plus a yellow sensor wire, not needed on a Mac. The plug and some of the wire was cut off the original ATI fan and soldered to the corresponding wires on the Fan Mate power in cable after first cutting off the Zalman plug. Solder joints and the cut end of yellow wire were then coated with rapid setting epoxy (unable to find any suitable sleaving)
Problem 2:
The fan unit is held onto the graphics card with 2 black plastic thumb screws (4 included in the box) which unfortunately projected sufficiently from the back of the card to prevent the card from being inserted in the AGP slot. To reduce the height of the 2 thumb screws, I put the metal shaft in a 12v drill and used abrasive paper on a metal strip on the plastic end until the central hole became visible in the metal shaft, around 10 minutes per screw. This was sufficient to insert the card in the AGP slot and screw in the end plate fixing screw.
Speed Controller:
The Fan Mate 2 fan speed controller has 12v input and a variable output of 5V (silent mode) to 11V (full speed). The missing volt made me suspect that the unit also limits the start up current to the fan, and it would be prudent to keep it on a 12v feed. I was unsure if the ATI 9800 would have sufficient power to drive the Fan Mate 2 fan speed controller (which does heat up slightly in use) and the fan, so I measured the voltage at the card socket with the set up complete. The following readings indicate that there is enough power.
Power on - Fan Mate 2 disconnected - no fan operation - 11.98v at board fan socket
Power on - Fan Mate 2 connected - fan at low (5v) - 11.97v at board fan socket
Power on - Fan Mate 2 connected - fan at max (11v) - 11.96v at board fan socket
UT 2004 in demo mode - fan on low (5v) - 11.89v falling to 11.86v with use at board fan socket
I assume that it would be possible to connect a "Y" lead (Y power adapter cable) in the DVD 4 wire power feed socket and use the 5v supply to power the fan, and omit the Fan Mate 2 fan speed controller. However, I did not have such a "Y" lead to hand.
Notes:
The adjacent PCI slot becomes unusable as the space is filled with the cooling fins.
Traditional lighter fluid removes the original thermal paste without damage.
Conclusion:
The Zalman VF900-CU unit is well designed, efficient and in silent mode (5 volt supply) inaudible. Highly recommended.
Regards, Nick H.
(England)
Other Graphics Card Cooler Related Articles: For previous articles on other Mac graphics card Cooler swaps (including ATI 9800, X800, X1900, Nvida 6800, 7800GT, etc.) see the Video Topics page Cooling Mods section.
I welcome other Mac graphics card user feedback on cooling/fan mods, performance, etc.
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