X86 family of processors
I remember when I was in college studying electronic Engineering my professor said that if you learn the architecture of the x86 you will be able to understand the workings of any processor made. Now I admit that today's processors are still based on X86 architecture, I believe say the (486) is worlds away from say a 2.8 Ghz P4. Therefore, by studing the (486) will not help you understand the inner workings of an advanced P4 or its related north and south bridges. Any comments anyone?
To learn is life, living is putting to use what you have learned, death is when this process stops!