I know that you guys are with stuff like heat rise on top etc. but i give you my word that my case/cpu/Pci's are cool and with low noise .
Well i moded at least 15 cases for me and friends , windows , lights , 120mm's , 92' 80's etc Holes side , front , top, bottom but right now i hawe my Antec SX1040B like this :
1 120 mm hole in the bottom of the case with a 120mm 69 CFM panflo for exhaust.
2 X 33 Cfm original side Antec fans wich now i reversed and they Blow air in (intake) .
This is the best combination i ever made :
The 2 side antec fans blow air in parallel with CPU and top motherboard (3 degree less on CPU) and push away all heat made by motherboard , and the 120 mm in the botom is placed under the PCI cards and he suck all heat from PCI but he cools also the PCI's sucking out the cold air made from 2x 30 mm side Antec's .
Videocard is colled on top by the side Antec's (you can feel the airflow sliding over the card) and sucked in bottom buy Panflo , i hawe same overclocking results like when i had a 80 mm blow directly on card .
The small heat produced by DVD/CDRW is sucked by PSU exhaust fan .
I hawe awesome temperatures XP 1800 SK6 with quiet 4500 RPM Ystech fan idle @ 38 , full load @ 43 , System temp max 33/Celsius , those are today with room @ 24/celsius.
I had cases with top exhaust , front blow fans etc but i never had such cool CPU and PCI/AGP cards with this much low noise .