post #11 of 11
Quote:
Originally Posted by `br4dz- View Post
There are way too many variables to make it 100% true with every case. It is true that air will be pushed out via cracks/holes/openings, but it's a matter of how much.

Positive pressure will generally make hot spots and improper circulation, that's just how air/pressure works. Take a look at how weather works, when there is a low pressure system this is how you get most of your wind. The air is literally sucked from high pressure systems into the low pressure systems. Same works with computers, where your computer can act as a low pressure system with negative pressure, while the outside would be high/positive, allowed for a more natural airflow pattern. With negative pressure air comes in via cracks/openings instead of escaping via those openings. I'm not going to provide proof for this since it's basic physics, but you could look up are positive vs negative pressure and base your opinion/decision on that.

Now, positive pressure can show that some temperatures are lower, but it isn't painting the whole picture. Cards that do not have temperature sensors, such as a sound card, wireless card, any expansion card, RAM, mosfets/chokes on a motherboard, etc. etc. that DO NOT have substantial cooling on them such as a video card fan or CPU waterblock/heatsink, and generally aren't in the path of an intake or exhaust fan can benefit from negative pressure. Ways positive pressure would be better is if you had an intake fan pointed directly at all spots allowing for plenty of airflow to all components, but this goes against what most people want since it'll be loud, attract a ton of dust, and is impractical for the large majority of computer users. A simple 3 case fan setup is usually enough for most cooling needs, with a front intake, rear exhaust, and top exhaust. In a perfect world the front intake would larger and/or running faster than the rear/top exhaust.

I know how the concept of high and low pressure works. This still doesn't explain how hot spots are created with only positive? You could have a hot spot in your case whether is + or - pressure. Whether the air is being sucked in from all the holes/cracks or being pushed out, its still air flow just in a different direction.

As for dust, with a positive you can at least control air coming into your case using fan filters. With negative unless you plan on silicon caulking or wrapping your case in a giant filter dust will seep in through all the cracks and crevices.

ahh well I'm sure we could argue this for eons, since it's like a nerd's religion.

I think we can both agree certain ones are better for certain reasons depending on your case.
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The 2600k
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CPUMotherboardGraphicsGraphics
Intel i7 2600k GA-Z68XP-UD4 MSI ATI 6950(unlocked) XFX ATI 6950(unlocked) 
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Mushkin 997015 8GB(2x4GB) DDR3 PC3-17000 10-11-... Crucial M4 128GB SSD Western Digital Caviar Black 500GB Custom Watercooled 
OSMonitorMonitorKeyboard
Microsoft Windows 7 Ultimate Viewsonic VX2739wm Viewsonic VX2739wm Logitech G15(original) 
PowerCaseMouseMouse Pad
Coolermaster Silent Pro M 1000 DangerDen Torture Rack Razer Diamondback Everglide Titan 
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Creative xFi Titanium 
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