how much effect does it have on gpu temps when mounting the psu fan up or fan down?

[whipgeez]

as the title says really, just ordered the xfx 750w black edition modular psu(given up on ocz stealthxtreme 2 after the second one came back broken after rma, plus it's too loud and making wierd noises) for thursday and just wondering if to face it up or down

 

[whipgeez]

here's a pic of the bottom, the manual says it can face down or up

 

[whipgeez]

there are slits in the bottom, they are at an angle, it looks like they aren't there in that pic but they are

 

[whipgeez]

the crap one i have in now is facing up, it seems to be sucking in the cool air off my side fan, so if i mount it down the gpu should get more cool air from this fan

 

[whipgeez]

zalman z9 plus

 

[whipgeez]

ok thanks, so face down i think it is then

 

[whipgeez]

GREAT, this new xfx 750w black edition has a damn rattly fan too!!

i give up, i'm not rma'ing it again, this would be the 4th rma of my computer in 2 months,

*starts looking elsewhere*