Is this the best cooler setup for my case?

[firstrig]

Case : Antec GX700

I will be filling up all optional fan slots as well. The default setup looks like this (red arrows denote exhaust and blue arrows denote intake)

The fans on the top are 140mm fans so it seems like a lot of outgoing air. I assume that the former setup will create negative pressure in the case and lead to dust accumulation. Instead, if I inverted on of those fans to blow air into the case, will it be a smarter choice?

I was thinking more on the lines of :

Any help would be appreciated.

 

[HEXiT]

the first 1 is your setup. the second will cause heat eddies right next to the cooler.
the flow rate of the fans will decide whether theres a slightly positive or negative pressure in the case.
so as long as the 140's run slower and have a similar but preferably less overall cfm ratings you should have a positive pressure. which is best to help keep your innards dust free.
although a slight negative pressure is better for cooling you will pull in more dust around the case joints which will negate some of your filtering..

 

[firstrig]

a slight negative pressure is better for cooling you will pull in more dust

Alright, let's do some creative thinking on the fly. Let's say we use an air conditioner mesh filter for all the fans (these are typically better at blocking dust than the stock filters that come with computer cases, not sure how much airflow they will block), what will be the best performing setup, now that dust is out of the picture?

I will add filter piping to the edges and case joints and basically cover up all orifices if that's what it takes.

Will this work or am I being too optimistic?

 

[HEXiT]

the top 1. because as i said number 2 will create a heat eddy just by where your ram is.
which will create a hotspot just over your ram and by your cpu cooler. this will reduce the cooling efficiency of any part that the hotspot moves over.

better to have a slightly positive pressure like i first said mate. that way theres no need for extra measures to seal the case because dust will always find a way in regardless of any measures you take when you have a negatively pressured case.
the top 1 is the correct mounting config. number 2 is a fail regardless of positive or negative pressure because of the potential heat spot issue.

 

[firstrig]

the top 1.

Is this constant across all types of coolers? I am using a Thermalrite Venomous X heat sink right now. Will it be a factor if I change the cooler to a low profile closed loop water cooling solution?

Another thing, as per my humble understanding, I think positive pressure is when there is more air flowing into the case and less air leaving it, which is what I was aiming to do by pointing one 140mm fan inwards. Wouldn't the first setup create negative pressure if both the 140mm fans (and an additional 120mm rear exhaust) blow air out as opposed to only 3 fans (+1 PSU +1 GPU) drawing fresh air into the case? The PSU and GPU fans are inside the case so they don't exactly draw in any additional fresh air, they just circulate whatever is inside and 2 of the 3 intake fans happen to be front intake fans which are severely obstructed (honeycomb mesh, dust filter, HDD and so on).

 

[HEXiT]

mate its simple physics. hot air rises. if you blow cold air down through it you create vortices's that trap heat. so you get hot spots.

positive pressure in the case means the air is getting pushed into the case and is pushed out. reducing the efficiency of the extractor fans.

negative pressure pulls air into the case and is pulled out. reduces the efficiency of the front intake fans.
so the preferred method is actually to balance your air flow as close as possible. so if you have 220 cfm coming into the case you want to push the same out. you can achieve this with controllers or doing the math.

most cases are setup so they pull air in at the front bottom and sides and eject it out the top and back. this is the most efficient method of dumping heat from the case.
yes occasional you will see a case that has a different layout but more often than not its a compromise to fit other parts and keep them cool.
you could for instance put a closed loop cooler on the back fan and have it suck air into the case but you will still have to eject it out of the top. the draw back is that if the fan is to strong it will blow warm air into the front drive bays causing them to heat up. not good.
so stick with the tried and tested number 1 solution it really is your best option.