Filtering top fan in P180

[beatle]

I just transferred my system into my new P180 last night. I've read that the top fan should actually be an intake and the rear fan should be exhaust. This is all well and good, but how does it affect dust? Should I scrap the idea of using the top fan as an intake and instead use the front fan for intake?

 

[Zepper]

Top intake fan, hmmm... Coke, beer, chips, peanuts - what else could it intake? Do you hold drunken parties, hmmm? Ashtray, urinal... If it was mine, I'd be blocking off the top hole.

.bh.

 

[beatle]

My comp is under my desk and out of the way of my table scraps for the most part. All of my drunken parties are out-of-house. I know where to pee and I don't smoke. My idea to use the top fan as an intake was based on this article. Not worth it?

 

[Zepper]

Seriously, most of the air coming in from that fan would immediately exit thru the rear fan, pretty much negating any contribution to case cooling from either. Just experiment and see which way works better.

.bh.

 

[beatle]

With further reading of the article, they conclude the same:

This configuration takes advantage of the large size of the Ninja heatsink. Because the Ninja fills almost the entire width of the case, air drawn from the top vent by the rear fan is forced to travel over the fins of the heatsink. A lower profile heatsink would benefit less from this configuration, and a great deal of air would be needlessly sucked through the case without ever cooling anything.

I'll just block it off and turn on the front intake to balance the airflow. It's already filtered.

 

[RallyMaster]

I would block it off. There's really no point to having it since the rear exhaust takes care of most of it anyway.

 

[beatle]

Yeah, I put some black duct tape over it and then installed the "spoiler."

 

[pkme2]

I have top 120mm fans on my PC-60s blowing outwards.

 

[Griswold]

I put a fairly low RPM (1000-1300) exhaust in the top slot. If I block that hole, all the temperature readings go up a notch, despite having a 120x38 exhaust in the rear slot.

 

[Dman877]

I tried blocking mine off but the temps went up a bit. It seems like having both rear fans exhausting air at the lowest speed setting was roughly equivalent to just the rear fan exahusting air at medium speed. The 2 fans at low speed are quiter so I went with that. /shrug. It seems like a no-brainer that having an intake fan blowing air right over the cpu from outside the case would cool it better but I didn't find that either. Maybe it's cuz I don't have a tower heatsink (I use a Zalman 7000).