I mean 3B is a large number ,how to design and even count them?
Well…I am really like I am five.
In: Engineering
For design you’ll usually be using a suite of [EDA (Electronic Design Automation)](https://en.wikipedia.org/wiki/Electronic_design_automation) software – i.e. software specially made for that purpose. Be aware that modern CPU design is a *very* complex beast on a *very* small scale. The software will give you all the relevant details (i.e. how many transistors there is in total) – nobody is counting them manually.
However, if you want to play around with creating digital circuits yourself, you can get an FPGA board with the associated software. An FPGA board is a programmable circuit with digital components, meaning that you can create a simple CPU if you want to – without building customized hardware to test your design and see it come to life.
[Xilinx (owned by AMD) is one common provider of FPGA boards](https://www.xilinx.com/products/silicon-devices/fpga/what-is-an-fpga.html) you can purchase and play around with.
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