hehe it could also be that it outlasts other parts.. you just never know.. the main par was not cracked (the part in the middle) so you are at least lucky on that part.. like the other person said it may work for 5 minutes to 3 years.. it may last a lot longer.. you just don't know.. but I have never seen that kind of damage before as it should be under the cooler.. so its weird its broken. the person you got it from probably sold it to you because they broke it and it was still working so they could get a new one that didn't have a busted chip. I would just be sure to realize that you may have to replace it sooner then later.. or years from now.. being you really don't know.
I actually bought it half the price its worth and the guy i bought it from had it second hand and he said he didnt need such a powerful laptop. And he definitely didnt know. So we both fell into someones trap lol.
Well considering its been running for 2 years now in my ownership and could be 3-4 years old in total it may keep running really. Maybe its not si bad after all lol