Is this a fault of my computer?

 From:  Rudy
Hello all,
hello Michael.
Rudy here.
I am not sure why this is happening....probably is my computer....
I include a file.

I want to boolean diff. the inside of my ring (using the cilinder), to get rid of the base of my rectangular head.
When I do the operation (first select my base obj....ring), then the obj. to subtract (cylinder), my machine start to calculate, for approx. 30 seconds, then the inside cylinder disappear, but the base of my head is still sticking down inside my ring. Somehow the boolean diff. did not happen
Am I doing soemthing wrong or is my machine ?(I feel it doesn t have memory enough to perform certain operations...bought a couple of 1GB memories to install.....)

Thank you,