# Define please! Serial ATA/300, Serial ATA/150, Ultra ATA/100



## pietro79

Hello,

I'm feeling a little dumb. It's proving difficult to find a clear answer. 

I'm looking to buy an internal hard drive, to put into a cabinet, and use as an external hard drive (to save some money)

I've come across the following names and I don't know what the practical differences are...I'm worried about compatability issues... what're the differences between these... and assuming there are no compatability issues, is one better than the other?:

Serial ATA/150
Serial ATA/300
Ultra ATA/100

I would give you my computer specs, but don't know which would be useful, so ask me if you need

Thank you!

Sincerely,
Pietro


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## colt1911

What type of cabinet do you have ? Most take an IDE drive but there are some that take Sata. Here is an article explaining the difference (http://findarticles.com/p/articles/mi_m0BRZ/is_11_22/ai_98977132 )


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## pietro79

colt1911 said:


> What type of cabinet do you have ? Most take an IDE drive but there are some that take Sata.



I don't have a cabinet yet. I will be pruchasing it depending on the hard drive. But yes, I'm aware I need to match the cabinet's internal connection to the hard drive... IDE or SATA

BTW, SATA is newer/faster connection, correct?

But, so, what about the differences between the 3 terms I mentioned in my above post?

-pietro


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## Cromewell

Yes SATA is newer/faster but for an external drive you will be limited by the USB bus not the drive interface. If your computer has eSATA you could use that and it will be quite a bit faster than a USB external drive.


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## pietro79

So what's the difference between:

Serial ATA/150
Serial ATA/300
Ultra ATA/100

?


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## Cromewell

Mianly the interface speed. ATA/100 also has 2 drives per cable were SATA is 1 drive. The interface speed is 100MB/s for ATA, 150MB/s for SATA150 and 300MB/s for SATA300. The drives will only hit the interface speed in certain situations (ie short cached reads), the sustained transfer will be roughly the same for all 3.


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