I was wondering if I would make sense to keep the top fan of my pc on. I have a scythe mugen 2 in push/pull and a top 140 mm fan and back 120. The case is a storm scout (I have also mounted a side fan , and the top fan is nearly touching the heatsink. I was wondering is the top fan is only disrupting the airflow, or if it would be helping as well. I know the best way to find this out is just by turning the fan off and seeing, but I wanted to see someones opinion and mull it over while I am at work.
(note, I haven't fully finished overclocking and I think I should be able to lower the voltage and keep it stable at 3.9, and mabye lose a few degrees loadwise)
load w/ gpu at load:54-55
(prime 95 to load, GPU is GTX470)
I had a similar setup. I used the Scythe Mugen 2 fan to push air into the fins from the bottom, and then the top case fan to pull air out of the case (exhaust).
Kinda had a "stream" of air going thru the HSF and out the case. I though it was very efficient. I could look straight down thru the top fan, and see the bottom fan spinning/pushing.
If your case top fan is too far off to be it line with the HSF, leave it on (exhaust), but have the HSF push thru the fins towards the back fan, and the case back fan pushing air out of the case (exhaust). This may or may not be in the way of the RAM. If not, it'll also help cool the RAM, as pulling air across them into the HSF.