Questions on fan placement on Corsair 650D

[swmlon]

I have recently purchased the Corsair 650D and have read around about the merits of positive air pressure in the case for improved cooling and particularly keeping dust away.
I've read that the supplied 200mm are not the best, and that fitting a decent 200mm fan like the Coolermaster Megaflows since it won't fit at the front intake.
So, thinking about how I could create a positive air flow setup, I was thinking of getting the Silverstone SST-CFP51B, putting on a Scythe GT AP-15 and hooking up my drives to this, then removing the drive bays entirely and then installing the Megaflow so I'd have a 200mm and 120mm for intake.
I was then thinking of removing the top 200mm fan, sealing the top cover so that there is only the rear 120mm for exhaust (that I'll probably replace with a Scythe as well.
Do you think this would create a optimal positive airflow and minimise the amount of dust getting into the case?

[Pob255]

umm the simple way would be to flip the top fan over so it intakes air.
You will need to get a filter for it though to keep dust down.

You do need to be aware that cooling can suffer with positive pressure.

I'm not that convinced that the coolermaster megaflow will be much different, it's deeper so wider blades but the rpm is lower.
the fans in the 650d are decent AFAIK, it was the lower rpm fans in the 600t which are a bit weak

[Noxvayl]

I have a Coolermaster CM690 and only use 4 out of the 7 case fan slots provided(all the others are covered with tape so no air can get out of them). I have also added Akasa acoustic absorption mats on the side panels and parts of the top to reduce noise. All together this creates a flow of air that starts at the bottom front of the case and exits at the top back. My CPU cooler(Thermalright Ultra eXtreme) is oriented horizontally to fit in with this flow moving upwards to make everything in my case aligned with the airflow.

To create positive pressure I use 45 and 70 CFM fans on intake and only 40CFM fans for exhaust. So more air comes in and less goes out but it all flows in the same direction. There has been a massive reduction in dust in the case and cooling is still performing very well.

Admittedly I am about 5 degrees hotter on the motherboard and about 1-2 degrees hotter for the CPU and GPU but dust causes far more problems than a few degrees. My next change will be 100+ CFM fans for intake, but they are expensive.

To answer your question I'd take the 120mm fan off the back and cover that opening with black tape, or anything else really. I'd then get some low RPM low noise fans for the top exhaust(I choose Enermax T.B. Silence) and leave it like that; later on you can add high airflow fans like the Akasa Viper or Apache to replace included intake fans. I think you can put 2x 120mm or 140mm fans at the front, which would be better imo.

By the way is there a slot to put a fan at the bottom of the case, near the PSU?

[gwyn]

The 650D has no option for fitting anything other than a 200mm at the front.
The supplied fans are very poor and noisy. When you put them through a fan controller, you get a strange electrical noise from the fan.
Im am running the standard fan at the front, soon the be changed to a Coolermaster magaflow. it is put through a fan controller.
I have taken the top 200mm out and just running the back 120mm also through the fan controller.

When just surfing, I turn the front fan off and the back fan just turning and here are the temps:
cpu-34c mobo-36c gpu-37c

When gaming, I turn them both to full and I get the following:
cpu-32c mobo-34c gpu-46c

So Iv got a silent pc when not gaming with good temps.

[Noxvayl]

The top of the case clearly offers the option of 2x 140mm or 120mm fans instead of the 1 big 200mm fan, this can be clearly seen by the last picture on this page> http://hexus.net/tech/reviews/chassi...hassis-review/

Considering the size and shape of the intake vents for the front I would of thought the same option would be provided. It's a shame if they haven't, silly oversight in my opinion.

Personally I'd move your 120mm fan to the top, be of more use there in my opinion. When you get your Coolermaster Megaflow you should look at getting 2x 140mm silent fans for the top. I use 2x 140mm Enermax T.B. Silence fans and they can't be heard even at full speed.

[gwyn]

Yes there is the opion for 120 & 140 on the top but not the front.