PCI Slot Fan - where to buy?

Hi-

Most important is that the PCI slot fan exhausts- that it isn't just an air mixer. Next, to get the most cooling, you'll want as many cfm's as possible. There are all kinds of gimmicks, and brand names like Thermaltake and Vantec have their versions.
I think the following is a reasonable performer, and has the desirable form factor

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=39598 &CatId=804

The following Thermaltake has high cfm's, but may be a bit loud:

http://www.aerocooler.com/shop.cart?action=ITEM&prod_id=FANTT2375

At 32 cfm though, it would really help exhaust hot air from inside the tower, and help the PSU (and other components) run cooler, and perform better.

Here's a 21 cfm version:

http://www.frozencpu.com/products/5947/fan-302/ThermaltakePCI_Slot_Fan_Blue_LED_FanA2426.html?tl=g40c18s62&id=4IGEJKpc

I use this one in my MDD G4 and I don't notice any additional noise.

http://www.frozencpu.com/products/3681/slf-01/BlackSlotFan.html

When I first installed it, I noted that it didn't seem to be pushing out very much or very hot air for a 42 cfm fan. Then I noticed that the PCI card slot covers are all perforated and the slot fan ***** in as much outside air as inside air. I taped over the perforations on the unused PCI slot covers and now the slot fan throws out a lot of hot air.

Carl B.

perforations? What do you mean by that? I run a slot fan also, and my temps are now at 94.9 degrees fahrenheit.

At least on my MDD G4, the PCI slot covers over the unused PCI slots are full of holes/perforations. This was undoubtly done by Apple to increase the exhaust to atmosphere area in the back of the case. However, if you use a PCI slot fan and have one of those perforated PCI slot covers adjacent to the PCI slot to which the PCI slot fan faces, the slot fan pulls in air from outside the case as well as inside the case. Using a solid PCI slot cover or simply taping over the perforated cover will block that outside air flow back into the case and into the slot fan. That makes the slot fan pull more hot air from inside the case and discharge it.

On my MDD G4, I could feel a significant increase in exhaust air out of the slot fan and in the temperature of the exhaust air out of the slot fan after taping over the perforations on the PCI slot cover on the fan intake side of the PCI slot fan. YMMV.

Carl B.

Hi, I am still not following. Perhaps, take pic of what you are talking about.

Question for you. What if all my PCI slots are used up, and have no empty slots? Then will the PCI Slot fan do its job? I have my fan installed next to the video card. Was told that the fan works better if next to the video card.

Also, I have a medium size case fan standing upright underneath the drive cage of my MDD machine. When I feel underneath where the 4 holes are, its VERY frigid under there - meaning, it feels very cold.

Now, is there a problem on redirecting the fan to face the pabst fan?

If you are using all of your PCI slots, including one for the slot fan, then you don't have to worry about perforated PCI slot covers as you obviously don't have any. Your arrangement is optimum for use of a PCI slot fan in a MDD G4 (i.e., in the slot next to the AGP video card) even though the fan is pulling hot air from the back side of the video card. Ideally, one would want to pull are from the front/VPU side of the video card, but that is usually not possible because of the MDD G4's physical configuration.

I don't think I fully understand what you are asking regarding redirecting your medium size case fan. In general, one should attempt to move air in a MDD case from the front and sides to the rear. Also, remember basic fan laws (i.e., fans in series increase pressure, not flow volume (cfm), and fans in parallel or just a bigger fan increases flow volume, not pressure). Usually you want to increase volume, but in a highly restricted exhaust environment, you may need to increase pressure in order to get the fan moving air volume at its designed flow rate.

Carl B.

Ok, should I just lay the fan down on its back on top of the power supply towards the front in the back? I don't have a lot of modding skills as you can see. It was just an idea of mine to put another medium size fan inside my machine. Where would you recommend I then move it to if not underneath the drive cage facing the pabst fan?

Also, if I decide to change the case fan(large pabst fan), is it easy to remove the entire assembly and replace with a silent-x fan? The noise, though not really loud, is starting to get on my nerves.

power supply fans I am not gonna touch!

Japanmac,

I just had to replace my pci slot fan. The original one I Had from one of my PCs died. I got one which has an air flow of about 42CFM. I believe the other one was a mere 21CFM. What is the difference between the different CFM's and also is 42CFM going to assist a lot more in cooling down an MDD machine quickly?

If this slot fan is really powerful like that, I just might remove the large 80MM on top of the roof of the optical drives. Its blowing upwards.

I had to replace mine also.. I got a 42CFM over the older 21CFM. Does it work this way? The higher the CFM number, the greater the cooling will be?

I do hear some noise from it, or maybe its that large fan I have mounted on top of my optical drive roof.

Hey Nadav,

the new fan is moving twice the amount of air (Cubic Feet per Minute) as the old one, and the more cool air you can draw in and hot air moved out = cooler Mac. I'm running a PCI slot fan on mine as well to draw some of the heat from the Radeon 9800 out and it helps.

I'd get rid of the 80mm fan - the PCI fan will take up the slack, and I doubt it was doing much for you anyway.

-Douggo