Best fan configuration?

[soulesschild]

I currently have a thermalright SI-128SE and a s-flex fan ontop of it. I was wondering what's the best way to have the fan, pulling air from the heatsink, or pushing air onto the heatsink? Here's a picture in case you like visuals.

 

[Logan321]

Usually you'll get a cooler CPU temp but higher motherboard temp by blowing towards the board, and opposite effect from blowing away from the motherboard. If you're not overclocking too much then blowing away is fine but for highest OC with lowest temp, blowing towards the board is probably best. Try both ways and check the temps though.