Re: Upgrading a psu and graphics card?
To point you in the right direction, I would use a 430W builders series >>> Corsair <<< power supply and perhaps an Nvidia 9800GT graphics ??? What slots do you have on your motherboard ? (PCIE ?)
For FSX you might need something more powerful like a GTX460 perhaps. The power supply power should be enough just however to future proof your PC you could go for something like 600 - 750W.