FS9 performance,better graphic card?

Just wondering...
I have a quad core amd athlon 2.2 cpu,and FS9 has fine frame rates-whilst my onboard 256mb card is on performance that is.
Just installed Brize Norton,and frame rates are only 8-10 per second at times.Would a 512mb card enhance frame rates on my PC,for FS9 ? So that i could have the slider nearer 'quality' ,also ?
Any advice most welcome.
Jon 8-)
I have a quad core amd athlon 2.2 cpu,and FS9 has fine frame rates-whilst my onboard 256mb card is on performance that is.
Just installed Brize Norton,and frame rates are only 8-10 per second at times.Would a 512mb card enhance frame rates on my PC,for FS9 ? So that i could have the slider nearer 'quality' ,also ?
Any advice most welcome.
Jon 8-)