Need Clarification about Ext. HDD

Hi guys, I just need some clarification about using external HDD (either using an enclosure or not). This if for my A8Js.

1. For HDD rpm issue (say 7200), if I were to buy one and connect via usb 2.0 or firewire first without using an AC adapter I would not be able to appreciate the full speed/loading/reading time of the 7200 since it has to travel via usb/firewire. However, if I were to use one with an AC adapter would it be the same?

2. Trying to achieve full 7200. From what I've been reading, the best way to achieve full speed is to purchase an expresscard SATA adapter then buy an enclosure or HDD that connects via serial ports (eSATA). If so, would it matter if the enclosure or HDD has an AC adapter or not?

Hopefully that makes a bit of sense.

Thanks!

 

First of all you have to decide what type of external hard drive you want.

You can buy external 2.5" HDD (the ones used in notebooks) which can be powered by usb without ac adaptor/power. Its small, light and can solely be powered usb port(s). Its more expensive than external 3.5" HDD (used in desktops PC's) and is limited to 200GB (4200rpm), 160GB (5400rpm) or 120GB (7200rpm). Performance is not as good as 3.5" HDD. USB 2.0 (practice, not theory) is just about enough bandwidth for notebook drives and won't bottleneck the performance much. Firewire is slightly better...

If you go with external 3.5 HDD and require high performance then yes usb 2.0 (again practice, not theorectical limits of the interface) will bottleneck the performance of the drive. External 3.5" require addtional power through AC so they're not as portable.

My advice if you're going with desktop drives and want performance then eSATA and firewire 800 (ieee 1394b) is the way forward. If you don't mind performance then usb2 and firewire 400 is enough...

 

What will you be using it for? If your not looking to use this drive as a mobile unit, then you may also look at getting a NAS drive.

Otherwise the interfaces are like this : eSATA > FW 800 > FW 400 > USB 2
Pretty much everything ez said is spot on.

I have used external 7200 rpm 3.5" drives over fw400 and usb2 as well as a 7200 rpm 2.5" drive (60 gig) on fw400 and usb2. I don't see much difference between either drive. I can actually play games off the 2.5" drive (I was using it to play Dark Messiah of Might and Magic). It can transfer over a gigabyte a minute. So it is fast.

Go with eSata or FW800 if you plan on doing A/V editing. Otherwise I could not see the increased price in either a eSATA case and card or a fw800 case being justified over fw400 or usb 2.

 

I am using the extra HDD as a non-mobile storage unit. Basically hold all my crap, and stream from it. If there isn't a huge issue with speed, I guess firewire400 and usb 2.0 maybe good enough.

Just want to ask one more silly question, if there is a backup button, does it work like this? If I have 100gb, it will backup additional 100gb on the remaining space. If so, if there is no space available it will not backup?

Thanks

 

With some backup software, it will start overwriting the oldest backup set when it runs out of disk space or when it runs into a set amount of usable disk space.