CISC VC RISC Processors for Dummies
There are two types of processor architectures: RISC (Reduced Instruction Set Computer) or CISC (Complex Instruction Set Computer). An “instruction set” is basically what operations a processor knows how to do without any prior programming.
When you have a larger instruction set, the processor accomplishes more complex tasks with fewer commands. Smaller instruction sets require more commands but execute each of them faster.
Let’s say you want your computer to make a buttered toast. Grab a slice of bread, some butter, and a butter knife, spread the butter on the bread, and place it on a pan. A CISC processor groups all of these tasks under the single “make buttered toast” command. A RISC processor, on the other hand, requires you to issue them individually.
However, there’s a cost to having more instructions built in. The processor needs to be more robust, and each command, as it’s more complex, takes longer. They also require more power to operate.
CISC processors were better suited for earlier days of computing. That’s because, back then, writing software had to be as simple as possible. Advanced tools, like the ones available nowadays, didn’t exist, so the processor had to do the heavy lifting.
In contrast, when RISC processors were created, in the 1980s, they were severely limited in their abilities. It was only in the last couple of decades that they started packing enough firepower to rival their CISC counterparts.
X86 Intel vs AMD Is Different From ARM Qualcomm vs Apple
Now, one may play the “What about the difference between Intel and AMD processors?” card. The answer here is: business decisions. It’s completely different from Apple Silicon chips compared to Arm-based CPUs from other manufacturers — and irrelevant to Hackintoshes.
The X86 instruction set was created by Intel, and AMD had to kind of reverse-engineer some of it back in the day. Then AMD created its own instruction set, with one advantage: it could process 64 bits of data per CPU cycle. That was roughly 4 billion times as much as Intel’s processors (though that doesn’t mean they were 4 billion times more powerful).
But AMD still didn’t have access to the full 32-bit instruction set created by Intel. It was used in the majority of computers and is still relevant to this day. So the companies reached an agreement: AMD opened its 64-bit instruction set to Intel, and Intel allowed AMD’s processors to be fully compatible with the 32-bit architecture.
That’s why you can run Windows, most Linux distributions, and, nowadays, even macOS, on both Intel and AMD-made CPUs. The “list of commands” each processor understands is the same, and the companies compete on other aspects.
