GP3 hates new radeons. Unless its a very powerful one, that can make up for GP3 hating it in brute force (essentially, a 9700 Pro or better). The 9600SE is a fine card, buyt not that powerful. Shouldnt affect CTDs, but it will hmaper performance badly. Make absolutely sure your quality settings are on 'performance' for GP3, ie no AA or AF, because GP3 really really hates that!
Also, right click on the Gp3.exe, and select 'compatability' tab, and Win98 mode. I've never known it to actually make a difference, but it must serve some purpose.
If you've updatd gp3 with a new track or carshape, if its a little dodgy, gp3 will get very crash happy, right at the point when the loading lights start going.
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She says brief things, her love’s a pony
My love’s subliminal