Look guys, basically I can just repeat what has been said: CPU is the most important factor for LFS.
BUT there is one special case where this is not true. And that is when the GFX card doesn't support HVS. And this is the case here, so upgrading the GFX card will be a much higher benefit for a much lower cost, because even a measily 9600 would suffice to fulfill the HVS requirement.
A 6600GT is probably too much for his rig, especially if he doesn't plan to update the other components in the next time, too.
A 9600 would be good enough for LFS, that's for sure, but I think he wouldn't be too happy with the 10% time he plays other games.
A 9800 Pro is probably the best choice IF he wants to play other "newer" games too. If the remaining 10% time is spent on Sim City 3, Civilization or something similar, then the 9600 would be more than enough.
BUT there is one special case where this is not true. And that is when the GFX card doesn't support HVS. And this is the case here, so upgrading the GFX card will be a much higher benefit for a much lower cost, because even a measily 9600 would suffice to fulfill the HVS requirement.
A 6600GT is probably too much for his rig, especially if he doesn't plan to update the other components in the next time, too.
A 9600 would be good enough for LFS, that's for sure, but I think he wouldn't be too happy with the 10% time he plays other games.
A 9800 Pro is probably the best choice IF he wants to play other "newer" games too. If the remaining 10% time is spent on Sim City 3, Civilization or something similar, then the 9600 would be more than enough.