CM RC-690 Fan Configuration

[Hawnted]

I have 7 Yate Loot D12SM-12 at my disposal although I am thinking of only using 6. I just bought the CM RC-690 for my server case. What would be the optimal fan configuration?

• I was thinking of two Front intake fans
• Two top exhaust fans
• 1 Rear Exhaust fan
• 1 bottom intake fan
• PSU mounted intake fan down, with exhaust out the back
• Leaving all the side fans empty

What do you think?

 

[Shadowssong]

Sounds good, maybe try to cover up the side panels to avoid dust being sucked in through it.

 

[Jason]

i have the 690. it's full of scythe slipstreams (for the vertically mounted spots) and s-flexes (for the horizontally mounted spots).

i've got:

2 front intake
1 bottom intake
1 side intake (bottom slot)
1 rear top exhaust
1 rear exhaust
psu intake mounted down, exhaust out the back

i can't utilize the top side intake because my heatsink blocks it. i'm not utilizing the front top exhaust because of the 2nd front intake i have mounted in my 5.25 bays. i figure an exhaust in this position will funnel away too much air before it has a chance to reach the push fan on my hyper 212+. (i'm running a push/pull on that.)

 

[XpediencY]

I used to have:
2 top for exhaust
2 front for intake
1 back exhaust
1 side intake
1 bottom intake
1 mounted on the HDD cage

Now I have:
2 front (in)
1 back (out)
1 bottom (in)
1 side (in)
1 HDD cage
and I taped up the top vents, and one of the side vents to create a wind tunnel and the effects are so much better than running so many fans. My experience though lol

GPU lowered by 10C, CPU lowered by 5-10C on idle.
Effects prove themselves on load, Prime 95 used to push my Q6600 @3.6 to 90C (winter weather in Texas), now it doesn't even touch 80C (summer weather in Texas).

 

[Hawnted]

I have always heard not to use the side vents because it disturbs the front to back air flow. I guess I will just have to play with it since you guys seem to be getting decent results.

Where are you mounting the fan on the HDD cage?

 

[Cruiza]

Doesn't SilverStone (and others I'm sure) claim that positive air pressure is generally best? I think they set up the top fans to be intakes, and the only exhaust is/are the rear fan(s) when the PSU is bottom-mounted.

 

[XpediencY]

from front to back, on the very bottom row, it's front panel -> fan (came with the case) ->HDD -> zip tied fan (added to pull heat away from the HDD) The fan is basically perpendicular to the bottom intake fan

 

[crowat]

Doesn't SilverStone (and others I'm sure) claim that positive air pressure is generally best? I think they set up the top fans to be intakes, and the only exhaust is/are the rear fan(s) when the PSU is bottom-mounted.

I was taught the same logic. Although it was due to dust accumulation. Positive pressure causes the air to move out of the case through the cracks. Thus you are not sucking up dust. Although you want to make sure you are using filters.

 

[InvisiBill]

I have intakes in the bottom front, the lower three 5.25" bays, the front top, and the lower side panel. I have exhausts in the two in the top rear corner (plus my GTX285's stock cooler). I'm not using the upper side panel (interferes with CPU heatsink), the bottom (interferes with PSU), or the CPU-rear (the one I had there wore out and got loud) fans.

Doesn't SilverStone (and others I'm sure) claim that positive air pressure is generally best? I think they set up the top fans to be intakes, and the only exhaust is/are the rear fan(s) when the PSU is bottom-mounted.

I was taught the same logic. Although it was due to dust accumulation. Positive pressure causes the air to move out of the case through the cracks. Thus you are not sucking up dust. Although you want to make sure you are using filters.

Same here. With positive pressure, you have more pressure inside your case, meaning that any cracks will be exhausting. If you have filters on your intake fans, all incoming air should be getting filtered. With negative pressure, air will be coming in through those cracks, and nearly impossible to filter.

I don't think there's much difference in airflow with positive vs. negative pressure. No testing, just logical common sense - __CFM is __CFM, regardless of which side of the case the fan is on. I do remember an engineer-type from a board back in the day mentioning some differences in cooling due to direction, as related to the old Socket7-style heatsinks with a fan blowing down on a bunch of fins. With the fan blowing down into it, the turbulence causes the air to sort of jumble around in the fins and do a better job of picking up heat. With the fan blowing up and "sucking heat away", it creates a low-pressure area in the fins, then the air from outside moves in to fill the void. The air sort of takes the smoothest path through the fins and out the fan, not necessarily picking up as much heat from the fins. I'm no expert on thermodynamics, but it seems logical to me.