My first question is this a laptop?
You put you had 894 MB of RAM that is way to low for FSX I am thinking you meant that the on board video has this much ram would make sense.
Ram does not normally come in that low amount I think that the lowest is 2 gig but I could be wrong.
FSX is a CPU speed and ram hungry program the faster the CPU the better and the more ram you have is better as well, and the faster the speed of the ram is better as well.
In case you are not aware of this the 32 bit operating system you have can only support roughly 3.2 gigs of ram even if you put 4 gigs in it. You can run FSX with this system but you will have to both tweak and adjust the sliders down toward the low end.
So it depends upon what you expect from your system. If you want to be able to run FSX wide open then you will have to update your system. I finally updated my system this past January. I spent around $800 to $900 on this system and by no means did I get the best of every thing I could.
I shopped around and wound up with a system that will last me for about ten years or so I hope. The speed of technology now a days one never knows what is around the corner. A good example is I bought a Intel Quad core CPU with a sandy bridge which was top of the line at the time, than 3 months later Intel released the same CPU with a IVY bridge which of course is better.
I believe that building your system from scratch is better than buying a store bought system because you can put what you want on it with out all of the junk they put on store bought system now a days.
The biggest advantage is you have the Windows install disk.
If you plan on going to a 64 bit system you might want to check on which version of FSX you get as at the time I got my system the deluxe edition was not compatible with windows 8 64 bit. Some people now say that they have the deluxe edition running on there system so I do not know
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