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HD Int./Ext. transfer rates.What r they?

By aadominguez ·
Reviewing the specs on a Hard Drive, I noticed it mentioned max. internal and external transfer rates. The internal transfer rate had 'media to buffer' enclosed in parenthesis and was set at 100 Mb/sec while the external had 'buffer to host' in parenthesis and was set at 46.7 Mb/sec. I thought when the interface was ATA/100, it was transfering info. from your HD to your CPU @ 100 Mb/sec. Can someone straighten me out? What about SCSI's transfer rates? Are those rates from the HD to the CPU?

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HD Int./Ext. transfer rates.What r they?

by Craig Shepherd In reply to HD Int./Ext. transfer rat ...

Firstly you'll never get 100Mb/sec out of an ATA100 Drive.
I'm not 100% sure on how they come up with that but I think it might be MegaBit rather than MegaByte, which means 100Mbit/sec is the same as 12.5Mbyte/sec.

Internal rates are how fast the HDD can move data around inside itself. For eg. when you defrag that's just moving the data around, and will be reasonably quick.
But going from HDD to HDD say, will be alot slower because it has to go through the whole info path to get there anddepends alot on how fast your system is.

SCSI rates are naturally a lot faster.
You can get two types. Normal and Ultra-Wide
Normal SCSI drives have a 50-pin connector.
Ultra-wide have a 68 connector and are much faster again.

SCSI also cost more than IDE but the performance gain is appreciable

I hope I've been helpful

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HD Int./Ext. transfer rates.What r they?

by aadominguez In reply to HD Int./Ext. transfer rat ...

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HD Int./Ext. transfer rates.What r they?

by kschang In reply to HD Int./Ext. transfer rat ...

Actually, the above answer is slightly incorrect.

The "internal transfer rate" is referring the speed the read head can transfer to the HD's internal cache memory. That amount will vary depending on the HD model.

The EXTERNAL transfer rate is the speed the HD can send the data (from internal cache if present) to the HD controller.

Those two are hard drive PHYSICAL specs, and is not really dependent on the interface (IDE or SCSI). Think of them as ENGINE specs of a car. The engine affects speed and acceleration, but is just a PART of the overall picture (tires, transmission, weight, etc.) Those two specs affects the overall speed of the HD, but in themselves, mean very little.

The interface, namely IDE and SCSI have several levels of performance depending on price and hardware (ATA33/66/100, etc. vs SCSI 1/2/Wide/Ultra/Fast etc.), and that's usually theoretical maximum burst speeds. In actual practice you speed will practically NEVER match the maximum given. SCSI currently has the edge as the latest is up to 160 Mbps.

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HD Int./Ext. transfer rates.What r they?

by aadominguez In reply to HD Int./Ext. transfer rat ...

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HD Int./Ext. transfer rates.What r they?

by aadominguez In reply to HD Int./Ext. transfer rat ...

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