General, yes and according to your pc specs I'm afraid that card won't even fit in your pc because AFAIK the 9550 is AGP and your mobo is PCIe.
it's strange that other games work fine. Have you tried reinstalling LFS? How about a lower res like 800x600? My old pc a Athlon 2100+ with 9600pro, which is a better card than the X300, struggled at 800x600 with about 8 cars. I didn't turn the settings down though, so maybe if you turned the settings down you could get a reasonable frame rate at a lower res.
it's strange that other games work fine. Have you tried reinstalling LFS? How about a lower res like 800x600? My old pc a Athlon 2100+ with 9600pro, which is a better card than the X300, struggled at 800x600 with about 8 cars. I didn't turn the settings down though, so maybe if you turned the settings down you could get a reasonable frame rate at a lower res.