I have been working on a computer for the last few days that is a few years old but would be used for playing Microsoft Flight Simulator X and it has been a bit of a battle.
First of all when I looked at the requirements it looks like it does not take much to run Microsoft Flight Simulator but in reality it takes a great computer and the best video card that you can get to run Microsoft Flight Simulator with the highest settings.
I started thinking that I could use a year old HP desktop but in the end that desktop had not slot for a new video card and as unacceptable as that seems I think it is a fact that many home users would never get a new video card for their computer so I guess I can ccept that. I found another machine, a Dell Optiplex GX 260 with a half gig of ram, a 2 gig P4 processor and an AGP slot. This better or worse is what I have sued for the Microsoft Flight Simulator install.
For a video card I got a $95 Geforce 7600GS this card has 256 megs of memory and is an 8X AGP so I am sure that I am not able to take advantage of the full memory bandwidth on a 4X AGP bus. I loaded the card, got the newest drivers from Nvidia.
So now after 15 or so gigs of a load of the Microsoft Flight Simulator X I get to test it out. The software is fantastic and I have fairly low settings so I can imagine how this would be with a really great card on the PCI-E bus that a new computer has. I can take off with any one of about 30 planes and helicopters from almost any airport big or small in the world and the graphics on high are stunning. The trouble is with this video card on AGP that I do not get good framerates on high quality so I have had to turn down the quality to get it to run well.