How to tell if a minimax search tree is computationally feasible using parallel computing
Plainly, evaluating $10^{19}$ positions is not going to be feasible in 7200 seconds.  But if you use alpha-beta to prune the search tree and have perfect move ordering you can get that down to around $10^{10}$, a number that looks much more reasonable given that chess engines on PC hardware can do a couple million nodes per second easily.  Since alpha-beta is a serial algorithm, you'll have to do more than just naively divide the search tree among processors to reap its benefits, but there has been a great deal of research in this area: start here.