increasing RAM won't help u anything better except loading bit faster than before but not graphics.
1.did u calibrated ur graphics ? if yes, try to to delete ur graphics file and try to recalibrate again and see any difference. Change all mirror options in ur graphics file to "0" and make sure the first line is kept 1 in ur graphic file inorder to see changes in game. if u find any good results then slowly change them to "1" one by one until u find difficult again. Mostly change ur resolution 800*600 in order to run in high quality game. In 1024*768 u can't run in high quality.
2.By any chance did u enabled AA and AF in nvidia control panel? if so disable them b'coz this video card CAN"T handle them even with GP4 also.
3.If not the above all then Go to nvidia site and download older driver possible before 90.xx or 80.xx series drivers and try to recalibrate in ur game and check.
4.And also check ur CPU usage in Idle Mode just to check no other programs or AntiVirus software is taking all resources.
try them and reply here
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