RAM allows the computer working space in which it can carry out it's processes.
RAM is not a miracle cure, but only a part of what makes a system work.
A computer capable of running a complex flight sim for instance, needs to be a balanced powerhouse of computing strength, with a fast CPU, Plenty of RAM and a good video display system, running on a decent mainboard which supports advanced features.
If you post your complete and detailed system specification, maybe someone here can suggest what will help your particular configuration. Don't spare the details.


Mainboard: Asus P5K-Premium, CPU=Intel E6850 @ x8x450fsb 3.6ghz, RAM: 4gb PC8500 Team Dark, Video: NV8800GT, HDD: 2x1Tb Samsung F3 RAID-0 + 1Tb F3, PSU: Antec 550 Basiq, OS: Win7x64, Display: 24&