• Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
    Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.

external drives, firewire or usb2?

M

MetalDwarf

[H]ard|Gawd
Joined
Jan 20, 2002
Messages
1,072
hello

i already have an external usb2 drive (actually 2 drives modded into one box) both WD 200gb special editions 8mb cache + 3 year warrenty

they are great drives but via usb2 HD tach and sandra show a flat line of 30mb/s across the whole disk. i assume this is due to the bottleneck of usb2 and that the drives are actually faster then this but unable to show it due to the bottleneck, i have a firewire port on my laptop but im not sure if its 400 or 800

im wondering if this 30mb/s bottleneck is about the max speed of usb2 or if its the chipset in the enclosure. also would a firewire 400 enclosure be faster then usb2? how about 800?
 
The max. data rate of USB2.0 is 480 Mb/s (60MB/s). [i'm can't remember if this is burst or sustained.]
The max. data rate of FW400 is 400 Mb/s (50MB/s sustained).
The max. data rate of FW800 is 800 Mb/s (100MB/s sustained).

This is at the archtecture level. One thing to note about USB is that it does not have hardware-level controllers. I.E., it uses your CPU when it transfers data to do parity checks and any other calculations that are nessecary. FireWire connections have their own dedicated processors and so do not need to use the system's CPU resources while transfering data. For this reason it's often the case that USB2.0 will by slower than FW400, especially if you have a slower CPU. If you need the cycles, don't go with USB.

I'd suggest looking at task manager and seeing how much your CPU usage spikes when you copy large files, or when you're testing your disks. If you hit 100%, then the bottleneck is probably in your USB2.0 connection and dosen't concern your HDDs. Upgrading to FW400 or FW800 will probably net you a higher data thoroughput.

FireWire 400 ports look like a USB port with one end looking pointy. The normal (USB-sized) connections have 6 pins (three on one side facing inward and three facing inward on the other), and the mini connections (much like USB Mini B) have five (i think!) Those look much smaller and are squarish.

FireWire 800 ports look about the size of an ethernet port and have four pins and a plastic 'fin' that devides the pins into two sets of two.

So, if you're worried about plug-and-play ability with other machines, go with USB2.0 since it's so common. If not, i'd probably go with FW400, just cause i don't like to waste cycles and am not worried about needing to use my hardware with other machines. You can also buy enclosures that have one/two/three connection types. I hope all this helped.

edit: Did you mean 30MB/s or 30Mb/s? I'd check with your disk mfgs, but isn't 30MB/s pretty decent?
 
USB 2.0 is 480Mb/s BURST and is a shared resource as well. I just put a FW800 card in a 1GHz Apple G4 and it takes nearly half as long to backup to the LaCie 500GB external drive (has FW400 and FW800 ports).
 
davidlem said:
USB 2.0 is 480Mb/s BURST and is a shared resource as well. I just put a FW800 card in a 1GHz Apple G4 and it takes nearly half as long to backup to the LaCie 500GB external drive (has FW400 and FW800 ports).
Click to expand...
Sweet, thanks for posting the correct info...! ;)
 
Also, check the CPU usage when using USB2. Compared to FireWire it added another 40% CPU usage on a 2.8GHz Xeon.

L
 
Another thing to remember is that those drives are probably 5400rpm IDE drives in that enclosure. Which wouldn't be able to do much better connected to the motherboard.
If you are lucky then you have 7200rpm drives.
And only lately have externals been coming with SATA150 drives.

So 30GB is pretty good....

Besides which - externals are not for working with - just backups and sneaker net stuff - so the transfer speed isn't as important to the manufacturers as reducing their cost. :(

[edit] I just noticed what drives you have..... My WD external was a 5400rpm.
For you the drives aren't the limiting factor.[/edit]

 
Not that anyone cares but I'd figured I'd mention.

Whenever I back up my 14gigs of music from my iBook to my W/D 7200rpm, 8mb cache usb 2.0 hard drive enclosure. That takes about 5+hours to accomplish. This maybe be because of the bottle neck that the iBook creates with it's 4200rpm hard drive. Not to mention the laptop heats up when making the transfer.
 
You must log in or register to reply here.
Back
Top