Not getting best out of FSX on new build??

[snadge]

Hi

my dads new build
(which is a core-i5 @ 4.5Ghz and GTX 460 with 336 cores @ 775mhz / 4000Mhz and 4Gb 1605Mhz Ram)
- is playing FSX quite well according to him but he has cars, boats etc on 100% and it still plays fine... this leads me to believe that he is not getting the best out of his FSX on scenery etc... he describes flying through london on a microlite, following traffic along road and not having any problems etc, scenery was great so he said... but, when I was at his house recently the cars did have an impact on the gameplay for me but I think thats when Autogen and Scenerey complexity were on dense->to->full -> we didnt like the way you could see tree's etc loading up into the scenery as you were flying so I lowered both to 'normal' which seemed a little bit better as it wasn't loading as much in.. the odd tree and building which didnt look as bad (and as unrealistic) when loading huge clumps of trees and buildings..

all other sliders in scenery etc were on full (AFAIR)

whats others thoughts on this?

is there a way to speed up the loading of autogen etc? we have the whole program on a really fast SSD so dunno how its that slow? perhaps it was just too much stuff to load, there must be a setting or tweak to make that can still load a fair bit of autogen without it loading it when its just a few hundred feet away, if it loaded it up at further distance it wouldnt be as noticeable, ive seen screenshots of flying with high autogen density, he has a high-end system that should cope (these sandybridge i5's are under-estimated by those that dont have them, they are extremely powerfull CPU's which match first series Extreme Edition i7's in some games and excell it in others)

we used the online CFG Tweaker, ive since read that some people get a performance hit from that tool..

others thoughts and ideas are welcome.