External HDD

[willy123]

Hi guys, I was thinking about getting an external HDD as I think my Vaio lacks space, and s only 4200rpm, which isn't great for gaming. If I get a 7200rpm external HDD and connect it through USB it will be restricted by the 400kb/s or whatever it is, so I was wondering if I would actually experience any increase in speed between a 4200 internal and a 7200 external. Thanks

[GBS]

This one is worth looking at. I've been planning on buying it for a while, but I keep buying other more urgent gadgets....:smileylaugh:

Mobile HD

[hazymat]

I thought USB2.0 has 480 kBit/s.  

Um... try 480 MBits per sec - big difference

No - the USB2.0 standard supports about 48 times what a very good external hard disk can sustain data transfer at, so seriously - don't worry about USB2.0.

My advice - get a Lacie drive from Ebuyer. Forget Dixons - you will always pay about 20 or 30 quid more than you should for something like this. And Lacie of course make the best external hard drives money can buy.

Get a 250Gb Lacie d2 extreme for 130 quid - an absolute steal considering its performance and the fact it supports firewire 400, firewire 800, and usb2 (or 1 if you like).

[GBS]

Now to try to answer the real question:

Which will be faster? This depends on the new hard drive.

The speed of a HD is measured in 3 ways:
1) Interface (external) transfer rate - usually 100MBps for most drives today.
2) Media (internal) transfer rate - see below.
3) Average access time.

The most important rate is the Media (internal) transfer rate as this is the limiting process.

To determine the media transfer rate (MBps) you need to know the "true sector per track (SPT)" and the rotational speed. Use the formula below:

MBps=SPT x 512bytes x RPM/60sec/1000000bytes

eg: Hitachi Travelstar: 7200rpm and an average of 540 SPT

540 x 512 x (7200/60)/1000000 = 33.18MBps.

Now this is the average transfer rate, it is faster in the outer cylinders and slower in the inner cylinders. For this HD the Max is 44.24 and the min is 22.12MBps.

HTH.

Edit: Just to clarify the speed of USB 2.0 = 480Mbps (small b, very very important) = 60MBps (big B, very very important). So as Seb said, USB 2.0 has a max of 60MBps.

Firewire:
IEEE 1394b = 100MBps
IEEE 1394a = 50MBps

Now remember the size of the B's really does matter....:smileylaugh:

[VAIOFAN]

Now to try to answer the real question:

Which will be faster? This depends on the new hard drive.
 
The speed of a HD is measured in 3 ways:
1) Interface (external) transfer rate - usually 100MBps for most drives today.
2) Media (internal) transfer rate - see below.
3) Average access time.

The most important rate is the Media (internal) transfer rate as this is the limiting process.

To determine the media transfer rate (MBps) you need to know the "true sector per track (SPT)" and the rotational speed. Use the formula below:

MBps=SPT x 512bytes x RPM/60sec/1000000bytes

eg: Hitachi Travelstar: 7200rpm and an average of 540 SPT

540 x 512 x (7200/60)/1000000 = 33.18MBps.

Now this is the average transfer rate, it is faster in the outer cylinders and slower in the inner cylinders. For this HD the Max is 44.24 and the min is 22.12MBps.

HTH.

Edit: Just to clarify the speed of USB 2.0 = 480Mbps (small b, very very important) = 60MBps (big B, very very important). So as Seb said,   USB 2.0 has a max of 60MBps.

Firewire:
IEEE 1394b = 100MBps
IEEE 1394a = 50MBps

Now remember the size of the B's really does matter....:smileylaugh: 

You no what that imformation is excerllent for my couson. Because he is Upgrading some of the Hardware in his computer and he wants more imformation.

Paul

[seb21__]

One Point is the energy consumption. Some VAIOs have problems with USB-powered drives. An own power supply would be a nice feature.

[rich912]

Excellent explanation GBS!

[VAIOFAN]

i new it, becasue i got an wireless mouse and a stand witch is a chargger that plugs in to my USB 2.0 port on my RS and i put it on charge for the night got up the next morning and it failed to charge.

it goes on and off!

I wounder why?????

Weird.:smileyconfused:

[seb21__]

I wounder why?????

Because your VAIO was complete off?:smileyconfused:

[VAIOFAN]

No my computer "VAIO" is always on 24/7 as been for 6months+
Becasue i got told from a numbers of people to keep your computer on becasue it keeps the Hard discs from wearing out.

And i dont have any screensavers, i made sure that i put the option DO NOT SWITCH hard disc and moniter(LCD) off on stand-by. (thats anther thing my ATI graphics card dosnt like the computer beening on Stand-by, ather when the computer as been on stand-by for a period of time, i come back to the computer and continuing what i was runing (appicating) on the system "The computer just switches off and reboots. Ather when the windows has started up i get a pop error message box saying the corse of this majer shut down was the ATI.

I rang up ATI to comfirm what happened they havent got a clow they ask me to run some program to check my Specifications and hardware to see if any error appered, witch the computer past the hardware test and drivers.

so any way, i got my AOL broadband connect to my USB port and the power from my VAIO "USB port" runs my ADSL modem and i get a little pop up on the screen saying "lost DSL connection" and i looked at the modem and the light "power LED" is not on. This only happens once in the blue moon. But the mouse chagger always been playing up.


Like i say again its werid.
Paul

[rich912]

Becasue i got told from a numbers of people to keep your computer on becasue it keeps the Hard discs from wearing out.

Who the hell advised you to do this Paul? Have you considered that other components have a limited life span due to use?