Old configuration built for OSX Snow Leopard

[Milanche78]

Hi,

 

I have this old configuration, looking for replacement.Back in the day It was recommended for Vanilla Snow Leopard installation

Intel E6300 
Gigabyte G41-ES2L
2X2GB ram

 

I am missing dedicated graphic card as it is dead now, but MB has one onboard.

 

My main question is 

Does OSX uses less ram memory than Windows and will this config still be usable, as otherwise i can only sell it for peanuts, if anyone would buy it.

Another question

Will it be possible to run OSX SL or another version of OSX without dedicated graphic card, only using onboard one?