Quote:
Originally posted by WebMasta33
We can't use the speeds of parallel ATA because it's parallel. It's alot more effort for the computer to time the signals to have them run down the cable in perfect parallel, vs a serial connection, where they can just stream down one after the other.
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Oh man, that had me laughing out loud. That is just so wrong it's mind blowing. Computers work in parallel best, if parallel is so bad why are the memory bus, the PCI bus, the AGP bus etc. etc. parallel? Because it's FAST. Serial is cheap, and slow, and better for long distances. It is not fast.
As for the more effort that's just such utter shit. Given that the PCI bus is parallel to read a parallel signal it just asserts read on the ATA interface, write on the bus and dumps the data. To read serial it has to pull it one bit at a time through a shift register until it has the whole thing, then dump that to the bus. So given ATA is a 16 or 32 bit (I forget) interface you need the serial to be clocked 16-32 times faster. To achieve a transfer rate of 100mb/s requires a clock rate of 800MHz (at one bit per clock) minimum for serial. Given you can probably get a few bits per clock it might only be 200MHz or so. Now consider, how much more expensive/hot/difficult to produce is 200MHz hardware than 33MHz hardware? I'll tell you, a LOT. Fibre channel costs a crapload vs uscsi for exactly this reason.
Final words - if you want speed get scsi, if you want cheap get ata put up with slow speeds.