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skeptical
Authored by: SOX on Feb 07, '04 11:18:39AM

You should not have seen any difference going from a 4200 to a 7200 drive on a firewire 400 connection. the connection is the bottleneck not the driver speed



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skeptical
Authored by: jcteo on Feb 07, '04 12:56:15PM

A couple of points:

- He replaced the INTERNAL drive with a 7200 rpm. I don't think Firewire is involved.

- FW400 can more than handle the sustain rate from a 4200 rpm, so it is NOT the limiting factor

- In many operations (including "find /" that the original poster mentioned), much of the time spent is in seeking, not transfering. The decreased latency of a 7200 rpm drive would speed things up even if bandwidth is limited by the bus.


-j



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skeptical
Authored by: dintal on Feb 08, '04 01:15:55AM

well, that's just plain not true.

ATA drives, whether 3.5" or 2.5", 4200 or 5400 or 7200 are at most ATA 133 which stands for the transfer speed. an ATA 66 drive is capable of push 66Mb/s while an ATA 100 drive is capable of 100Mb/s. On the other had FireWire 400 is capable of 400Mb/s transfer rate. FireWire 800 is capable of double the rate.



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skeptical
Authored by: eggman on Mar 15, '04 08:11:34PM

I think "skeptical" might have forgotten that ATA XX speed ratings stand for XX MB/s...notice the CAPITAL B meaning byte whereas the lower case stands for bit (which is used for firewire speeds)...this would make 66MB/s roughly (ok, exactly) 8x faster than 66Mb/s etc...i'll leave the rest of the math to you, but personally, i'd take 100MB/s over 400Mb/s



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Wrong!
Authored by: pasta on Apr 05, '04 02:31:32AM

You're a tool! ATA-100 and ATA-133 drives are capable of a maximum 100MB/s or 133MB/s. However, this is only achieved when utilizing the drive's cache, which is typically 2MB or, more recently, 8MB. After that, the SUSTAINED throughput drops off dramatically to the speed at which the information can be extracted or written to the actual platters. These sustained speeds vary among different manufacturers and different drives, but typically a 5400RPM drive is in the 15-16MB/s range and a 7200RPM drive is in the 22-23MB/s range. As a result, a Firewire drive can perform EXACTLY the same as an internal drive can EXCEPT for the initial 2MB or 8MB cache access. A Firewire bus is capable of 400Mb/s, which is 50MB/s. That's why when you create a Firewire striped RAID, you get almost double the transfer rates of a single drive. It's not exactly double because the Firewire bus reserves a portion of bandwidth for communications with devices, but it's damn near close.



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