I recently moved a Sawtooth G4 to PC ATX (coolermaster) case to cut down the heat and noise of the old case.  This involved replacing the original power supply fan with a quieter fan and installing front and rear 120mm fans.  I have a 1.6ghz G4 from Giga Designs with stock fans on heatsink, those fans combined with the two 120mm fans made this case mod noisy.  So I decided to water cool my system.  While looking I came upon this http://www.xoxide.com/thermaltake-silentwater-lcs.html which is the Thermaltake silent all in one water-cooling system.  The brackets included allowed me to secure to my processor without any modifications and installation was easy.  I took out both 120mm fans, front and rear, with the water-cooling radiator and fan placed in the rear 120mm slot.  It is much quieter now, and super cool!  It took me 20 minutes in all, and it works like a charm.  Cheapest solution for mac water-cooling.  Can't post pics since I don’t have digital camera.  Just wanted to let everyone know this is the cheapest and best solution for mac water-cooling if you have a G4 in ATX case.

that's pretty neat but theres a better way. evercool has a water cooler that runs just under 100 bucks and sits in a empty drive bay. the setup uses two raditors and can cool the CPU plus a GPU or harddrive. Uses two 80mm fans with fan controls so you can control the airflow. Right now I have one in my gaming PC and its keeping my AMD Athlon 64 2800+ that is highly overclocked at a nice 69.8*F. Soon I'm going to invest in another one for my G4.

So how are you going to mount the waterblock to the CPU?

The brackets provided with the kit allowed for it to fit on the cpu card without to much trouble.  The holes line up pretty close with the holes used to mount the Giga Designs fan, so you can just use the provided brackets to do this.  The water block does not sit completely centered on the CPU, but the whole top of the chip does sit on the block.  Before doing this mod the computer use to crash all the time, but this water cooling appears to have solved this!  So, I just lined up the brackets with the provided wholes, them use threaded bolts with nuts to secure to card.  Took me 20 minutes to do the whole thing, from fan/radiator installation to water block mounting.  This system was also good for me since I don't plan on water cooling the GPU.  Here is the case I used to do this http://www.compusa.com/products/product_..._micro_ATX_Case    .  Thanks for the info

I'm curious to know what design you had from Giga. I assume it looked like this one:
http://www.smalldog.com/product/35547

I have a Mercury Extreme from OWC:
http://eshop.macsales.com/item/Other%20World%20Computing/MEG42M1500/

I think the fans are making my Digital Audio a bit loud, and I was thinking perhaps this Thermaltake would fit nicely, as the design of the two cards look very similar. Do you have any pictures? Also, I'm not very excited about the prospect of switching cases. Do you suppose there is somewhere else I could mount the assembly in my case?

The cards look exactly the same to me, including the fans and heatsink, so the water block should fit with provided brackets.  I don't think you could put this unit inside a G4 tower, but it wouldn't hurt to try.  Putting my sawtooth inside the PC case was easy, the hardest part was drilling the mounting holes , and lining up the Video card slot and PCI slots.  I have to cut out one piece of metal, then I was good to go.  The Power Supply fit perfectly in the provided space with no modification.  The case conversion in my mind is worth it, go from 3 fans (1 120mm + 2 noisy smaller ones on CPU) to 120mm adjustable fan is a huge noise improvement.  For the G4 case the only place that might be able to hold the Radiator and fan would be underneath the Zip Drive and Power supply, all you would have to do is remove the 120mm fan and associated metal bracket.  Just my two cents.

Thanks, I appreciate the input. I'd love two get those new-years-eve noisemakers off of my processor card.

Tiny fans=low air flow.  Most of the G4 upgrades have tiny, fast fans.  Take em off!  Of course you need a replacement, which, yeah could be h20, but its REALLY not necessary.  Many designs will fit an 80mm fan.  My choices are a Sharkoon Silent Eagle 80mm or a Panaflo L model 80mm.  Sharkoons kick ass as they are sooo quiet but still put a ton of airflow out (most quiet fans blow, pardon the pun).  Panaflos are quiet, very reliable and cost less.

Sweet. I really do like my G4 case, so I think I'll go the fan route. Do you think it would be difficult to put either one of those onto a Mercury Extreme heat sync? I guess I wouldn't know where to make new "holes" (or spaces between the fins?) for the new fan. Also, I would be concerned that the power would not adapt. Most fans that I know of run off the same connection as a hard drive. The two small ones on my heat sync are plugged into the processor card with smaller connections. Would it be an issue to just use a spare connection from the power supply rather than the one from the card?

Man, I haven't dealt with processor fans since Socket 7 was cool (K62 ftw!). I'm out of touch!

The heat sink looks small. Can't you re use the old heatsink? Or is the CPU placement on the board in a diffrent spot?

Yes, I was planning on using the old heatsink. I just don't think the orgininal screw holes (for the smaller fans) will work for the bigger one.

I'm really liking the Sharkoon Silent Eagle, but it's really hard to find. These seem to be the only two places where you can get one:

http://www.xoxide.com/sharkoon-silent-eagle-2000.html
http://www.crazypc.com/Merchant2/merchant.mv?Screen=PROD&Product_Code=5661

Anybody done business with either company before?

Edit: By the way, tjw7676, I kinda hijacked your thread. Sorry about that.