I'd have to say its not RAM. RAM is random and so this problem wouldnt happen every time then.
As for the CPU, I might as well flip a coin, because mostly any problem you can blame on a CPU, you can blame on a mobo too. I'd much prefer NOT to replace either since its a core duo, and i dont have the money for that or a mac mini mobo.
I'd like to think it has to do with RR and iG4.
Funny thing is, everything works fine when i have the BU-353 disabled (well, everything minus actual GPS tracking), I mean, iG4 starts in RR fine and doesnt crash. hell, iG4 works fine outside of RR.