Mosfet and VRM cooling (Xigmatek s1283)

How important is cooling of the mobo mosfets and VRM's around the cpu socket?

I am looking top build a Lan rig using either the Asus P7P55D EVo or the Gigabyte P55 UDP4 ,and the i5 750 @3.8Ghz with a pair of G.Skill Ripjaws(PC3-16000) and the Xigmatek HDT s1283 cooler. The case I have is the Lian-Li PC A05N.

Due to the case design I will have to mount the Xiggy with the fan pushing air towards the ram and therefore the downdraft spoiler cannot be mounted to cool the mosfets and VRM's on the mobo. Running at a clock of 3.8Ghz 24/7 will the mobo be sufficiently cooled or should I look elsewhere for a cooler pushing air onto the mobo instead of the tower design?
Really like the Xigmatek though...

The biggest thing is to make sure the Xigmatek S1283 will even fit into that case. It's a rather tall cooler.

I don't understand why you'd have to mount the HSF so it would blow toward your RAM. That makes absolutely no sense to me. You want the fan blowing back toward the rear exhaust fan.

Looking at pictures of this case, It's not going to be a good case for cooling. It only has a single exhaust fan, and zero intake fans. So you'll be trying to push warm air out, but not taking in cool air.

EDIT: Apparently there's a second 120mm fan tucked into the front of the drive bays. However, it pushes air out the front of the case. Looks like that rear fan pulls cool air into the case. So I can see why you'd be mounting your HSF backwards. Can't say I personally like the design of that case.