If computer clocks max out somewhere around 5GHz, how is it possible for 100Gbit internet to exist? How does the computer possibly transfer that much data per second?
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Even though there are a lot of great answers explaining how CPUs process more than 1 bit per cycle and why the processor’s clock speed is not a huge factor, I think most are missing the point.
Your question is still interesting for other reasons and it’s related to how digital communications work. The ‘real’ question would be: how can a 250 MHz wave/signal (for example, Cat 6 Ethernet cable) be capable of transferring 10 Gbit/s Internet?
Apart from having 4 cable pairs, the answer relies on something called __modulation__. If you only send a single ‘1’ as let’s say a pulse of 1V (volt) and a ‘0’ as 0V, those 10G speeds wouldn’t be possible, since you’d be at most, limited to 250 Mbit/s per cable pair, as your intuition told you. BUT, there’s a trick: if your electronics are capable of differentiating more than 2 amplitude levels (let’s say 0V, 1V, 2V, 3V to keep it simple), then you can associate each of those levels to a pair of bits, i.e: 0V = ’00’, 1V = ’01’, 2V = ’10’, 3V = ’11’. This way, if you send one pulse of 2V and then one of 3V you would be transmitting ‘1011’ with only two pulses. That means, you can send DOUBLE the amount of information, using the same frequency (250 MHz). This is called PAM (pulse amplitude modulation).
More complex types of modulation can extend this concept up to 12 bits / Hz. (Look up QAM on Wikipedia).
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