Since I bought a Nvidia 6800 Ultra to drive my 30 inch cinema display I
was not happy with the extra noise my dual 2.0 GHZ G5 produced. The
noise came from the PCI fan and the 6800 fan. I tried to stop the fans
with my finger to determine the noisiest one, but they each seem to
make different kind of noise. I decided to swap the 6800 ultra fan for
a more silent one and see if it get's more silent.
I read the article on your site about installing the Arctic NV5
silencer (see related articles below.-Mike) but I wasn't impressed with the quality of this cooler (the 'gap' at the bracket for instance). The local computer shop (I live in the Netherlands by the way) did had the NV5 in stock but without the correct bracket, but they also had the Zalman VF700-Cu in stock which looked (and feels) very solid. I decided to buy the Zalman for 30 Euro's (about 25 dollars) and give it a try. (Here's a link to a dealer selling the Zalman VF700-CU from our previous NV5 page.-Mike)
Before I started the 'big fan swap', hardwaremonitor reported a
temperature of 60 degrees C for the GPU and 30 degrees C for PCI bay.
After playing Unreal Tournament 2004 demo for about 10 minutes the GPU
temperature went to 75 degrees C and the PCI bay temperature remains
Removing the original cooler was very simple, installation of the VF700
wasn't very difficult either. There where two things I had to solve
because Zalman didn't have a Mac G5 in mind when they designed this
1. The Zalman braceplate won't fit because the bolts are in the way of
the bottom of the PCI bay. Not mounting the braceplate isn't a big deal
in my opinion because the complete 6800 ultra is supported by large
metal brace of it's own.
2. The Zalman fan connector won't fit the Nvidia PCB and I refused
(because the ugly looks) to use the supplied Zalman cable. So I cut the
Zalman fan cable to the proper length and used seperate PCB connectors
with some shrinktube to connect the fan to the PCB (see photo). The
third (white) cable isn't used.
(Photo cropped - card is longer than shown - see below)
After the swap the idle temperature of the GPU dropped about 3 degrees
at idle and 5 degrees C in stressed situation, the PCI bay temperature
didn't change. The whole test isn't very scientific but the noise level
dropped to a level which didn't bother me anymore and as a bonus the
card temperature dropped some degrees.
I made a complete photo shoot of the fan swap, some photo's are
attached (see below) If you want more photos, please send me an email and I will send them to you.
Hans van Esch
(Hans sent a few other photos-Mike)
Other Feedback on this Cooler:
This 6800 owner used the VF900 cooler (There's a previous page here with photos of the VF-900 on a Mac 7800 GT)
Having recently upgraded to an Nvida 6800 Ultra Mac Edition in my Powermac
G5 and found it a bit noisy as well as heating up, I researched the matter
and also found the Zalman a choice product well suited to the task. I was
out for the VF700 Cu but however ended up with the VF900 Cu Led as that was
all they had.
The result installation was a sucess and the method is
identical to the VF700. I used as bottom bracket the small plastic
retainer of the original fan and it just snapped in securing the four small
Everything works including the Led on the fan which is rather neat
looking. The package comes with a fan adapter which I did not use and find
necessary. Overall I am very pleased with results having a drop of 10
degrees C from the previous as well as ultra quiet noise level. I would
highly recommend the VF900 Cu Led to anyone who wants a cooler and quieter
I too installed the Zalman VF700-Cu cooler, and I am *very* pleased
with it (I'd originally intended to send pictures and notes, but an
unfortunate camera mistake left me imageless and I've been too lazy to
My 6800 ultra originally peaked at around 66 (°C I assume-Mike) while gaming (UT, WoW) and
idled in the high 50s. Now the peak is 56, with an idle at 49-50 (I
used a very thin carefully-applied layer of Arctic Silver on the GPU,
rather than the supplied thermal paste).
(FYI: On the PC the Nvidia control panel notes the
(clock speed) throttle down temperature is 120°C on a 6800GT
and even higher on an Ultra card. I flashed a GT with Ultra bios
and I think it then reported 132°C as the limit IIRC.-Mike)
Plugged into the card, the cooler is *much* quieter than the stock 6800 ultra cooler. There really is no comparison... vastly better cooling and noise levels, a very good upgrade.
(I must be lucky, as the 6800 Ultra sample I have does not have a noisy fan in my opinion, but other 6800 owners have complained about fan noise.-Mike)
To add a bit to the installation notes, you can plug the Zalman fan
into the built-in power socket without any wire cutting, with a small
amount of careful work. The plastic guide around the two power prongs
on the card (that the original fan plugs into) can generally slide
right off the prongs, allowing the three-hole fan plug from the zalman
to plug right into the two-prong outlet without any trouble (just use
care to gently pull the socket off, not the prongs :P).
The colors on
the original fan wires make it obvious which side of the zalman plug to
use (red and black goes into red and black, just like you'd expect).
Since that power outlet is controlled by the card, it runs much slower
than maximum speed, making it practically silent. It's amazing that it
cools so well. You could probably get even better cooling by using
Zalman's power adaptor to plug it into the DVD/RW power plug (you'd
need a splitter, not included), but this cools so well at the lower
RPMs I couldn't see any need to clutter up the case so with that
method, let alone find justification to increase the noise level.
Highly recommended, and Quiet PC shipped it very promptly and
For other Mac graphics card related articles, see the
Video Topics page.
I welcome other Mac 6800 owner comments - please include your system/OS version and details on apps/games, etc. you used in reports. Thanks.