I was reading online that CPU cores can be less than a square millimetre per core. I’m wondering if we are going to reach a limit with how small we can compress them.
In: Engineering
We already have reached (in lab experiments) the limit for how small a transistor can be before quantum mechanics take over and electrons are as likely to pass through an off transistor as an on.
With transistors that size, the lower limit to the size of a CPU core depends entirely on how many transistors you want in it.
The upper limit to the size of a CPU core is generally set by how far an electric signal can travel in a single clock cycle. For a 3ghz processor this is about 6cm.
Edit to add: the limit of the size of a transistor is the size of a medium sized molecule, so the limit for how small a CPU core can get is probably around the size of a virus as long as you don’t need it to do anything but basic arithmetic.
When you make a Lego car you can build a pretty small car, and by using the smallest parts you can find and by reducing unessecary room between parts you can reduce its size.
But at the end you’re still using Lego, at some point making the car smaller would mean you’d have to remove a wheel and it would tip over.
The same goes for CPU cores, we’ll need to use atoms, and those have a fixed size, furthermore the core has to be reliable, so it needs proper isolants, to make sure an electrical current doesn’t jump between parts.
Not really. However, wafers will have flaws in them. Chips with flaws have to be discarded so chip yield goes down dramatically as die size increases. Also the instructions on single core can be pipelined like an automobile assembly plant and can also be run out of order to maximize efficiency, but you can only do this so much before you get down to the most fundamental steps. Lastly, you can increase the word size, but after 64 bits again you hit rapidly diminishing returns. Even with multiple cores you’re going to hit these kind of limits. For instance, you can only parallelize operations on a database so much before you can no longer guarantee internal consistency.
TL;DR: You can make it bigger but after a while it won’t help.
Latest Answers