8 bits make a byte. A 1000 gigabits / 8 = 125 MegaBytes. Most hard drives running at 7200 RPM should be able to hit at least 80 MB/s, if not 160 MB/s.
Resources
https://www.codeaperture.io/2020/01/05/configure-a-test-lab-on-a-unraid-working-from-home-part-i/
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