hi i am looking for a recomendation for a video card i have an hp 8034n athlon duo core 5000 3gb ram ddr2 400gb hd play a lot of flight sim games but right now have onboard graphics am looking at geforce 7900gs 8500gt and an 8600gt from bfg they have whats called thermointelligence cooling anybody heard of it supposed to run cooler than standard cards ? don't need a high end card but a real good midrange .hows the ati versus nvidia ? and choice between 256 and 512 mb memory.thanks.