importance of things other than gpu in gaming?

Originally Posted by jimmyhackers 

so far my 6 year old pc has held up very well with modern games and general life. it started out as my uni advent pc with an msi 7187 mobo
granted i have...
bought a better modular power suppply, maxed its ram capacity (4gb. 3.5gb in windows), given it a corsair h60 cpu cooler despite being unable to overclock it due to naff bios locks, bought it a ssd, went through a few graphics card and am now with a gtx 560 ti 2gb.
anyways the shorts of it is the only real hardware update that mades any noticeable difference to my gaming is the gfx card. however of late i noticed with my new gfx card i have the option of swapping the physx engine over from my cpu to the gpu and that improves performance drastically. whats exactly going on there?
i know i should just bin my mobo,cpu and ram and start afresh.
im just wondering how much difference in gaming i can expect from say buying aria's top "gladiator" mobo cpu ram deal? and keeping all my other components
i ask about gaming mainly as i feel my computer is still fast responsive and non glitchy in all other day to day tasks
any advice would be appreciated

Originally Posted by Captain_cannonfodder 

Sounds like a modifed pre-built. Toss out your old gear and get the CPU bundle. Keep the PSU and GPU, get a new case and get Windows 7 64Bit.

Originally Posted by jimmyhackers 

thanks for the replies,
my screen is a 50" i set it to pc mode for normal use/gaming and crack it to 3dtv mode when i want some intense fallout/black ops action
ive figured a few games dont run aswell as others in 3d mode. as a whole it runs pretty well but as always i want more
my mobo's pci express slot is only version 1 will this hamper its gaming performance? if so how much by?
its as i figured then, new mobo cpu ram, i already have win 7 64bit and i think ill keep i alienware case i transplanted it too. its old but its from the 80's like me
out of interest, and i know windows score index isnt much to go on. but my friend bought himself an prebuilt from a pc fare for 220 quid. core i3 with onboard graphics, windows 7 etc....
anyways i beat him on gfx and hdd transfer rate obviously but cpu and ram were better at 7.1 and 6.4 (4gb ddr3) respectivly. seeing as my current is at 5.1 and 5.3, is a highend prebuilt bundle really what i need? those overclocked bundles are 800 plus quid and i wonder how necessary they are.
will more or equal ram to my 4gb but in a ddr3 or ddr5 compared to my current ddr2 make that much of a difference?
my point is do i really need an overclocked bundle, am i better of buying the same or cheaper mobo cpu seperately but with say one 4gb stick of ram and maybe think about adding another in the future.
that price i think is because its prebuilt overclocked and tested. i dont think thered be much stopping me getting similar results with my h60 and im not affraid to plug things in and change a few settings.
another thing if i am looking at mobos and im contemplating getting a pci express ssd, does it have to be a paticular type of pci express slot? or have i just opened up a whole new can of worms there?
thanks again guys