it's megaherts * the data path in bytes. Well it works for stuff that doesn't use special technology to cheat for it's bandwidth.
SO if you take pc800 and multiply it by the databit path in bytes you get 800 x 2Bytes (16bit datapath) and thats your bandwidth. which is 1600MB/s. Thats if you don't use dual channel .. obviusly dual channel doubles the bandwidth.
samething with anything else ... Take the AGP bus of 4x which is 2^26 (66mhz) * 4x * 4Bytes (32bit datapath) = 1,073,741,824 B/s.
PCI bandwidth, take 2^25 (33mhz) * 4Bytes (32bit datapath) = 134,217,728 B/s
However you have to think of other technology involved too and find out what that does .. such as vlink .. .to be more accurate with current technology. to get the right bandwidth.
take PC2100, 2^28 (266mhz) * 8Bytes (64bits) = 2,147,483,648 (thats your PC2100) B/s OR 17,179,869,184 b/s if you multiplied it by bits instead. As you can see multiplying it by the bits gives you bandwidth in bits.
Lower case b always stands for bits uppercase B always stands for Bytes.
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