Transfer speeds with USB 2.0 external Hard Drive?

[jrichrds]

What kind of transfer speeds do you get when moving files to a USB 2.0 external hard drive?

It takes a little over 60 seconds to transfer a 700MB file to my USB 2.0 external hard drive, which seems awfully slow. This is on a 2Ghz PC, and both internal drive and external drive are new 7200rpm 8mb cache drives.

Is this the expected speed of USB 2.0 hard drives?

 

[Mday]

word is the ATA-USB converter built in the enclosures limit the speeds that the drive will work at. I have seen reports of 15MBps and 10MBps. usb 2.0 runs at 480Mbps, which is some 60MBps. ATA drives arent that fast anyway. 700MB in 60 seconds is some 11MBps. seems reasonable.

 

[jrichrds]

I timed a few large file transfers, and found the speed to be:
From internal drive to external drive: 9.3MBps
From external drive to internal drive: 14.9MBps

Which are right under the 10MBps and 15MBps numbers you mentioned. Maybe the ATA-USB chip is limiting the transfers to those speeds after all - rather dissappointing if true, since all the ads for external enclosures simply say "up to 480mbps." So I had thought transfers would go as fast as the hard drives could handle them.

By the way, my external enclosure uses the Cypress Semiconductor AT2 chip (4th gen) - supposedly the latest and greatest.

If any of you get faster transfers with your external USB 2.0 drive enclosure, post a reply. (along with the chip used in your enclosure if you happen to know which one it's using).

 

[LED]

Stating "up to 480mbps." is no different then the ATA and SATA HD's not being able to transfer at their 'up to speeds" (ala 100/133/150). Firewire is faster in realtime then Hi-Speed USB so my Cases have both. I think This one is from the Oxford chipset (maybe 2nd gen NEC) but the HD is an 80 gig WD SE (8MB cache)

 

[Zap]

I have a Coolmax aluminum external USB 2.0 drive bay. I've used a variety of current generation 80GB/platter 7200RPM hard drives in it and have been pleased with the performance. Sure, slower than hooked up natively to the IDE ports, but the convenience tradeoff is worth it since I often use it for hooking up various hard drives for data transfers and backups. It's not slow enough to be worth shutting down the system to swap in a hard drive, boot up for the data transfer, then shutting down the system again to remove the hard drive. Actually a current generation 7200RPM hard drive in a USB 2.0 bay performs like a past generation 5400RPM drive on an IDE port. Good enough to still run apps off it, but definately good enough for just raw data storage. Heck, if you're gonna run apps off it, better to just have another drive installed inside the system.

 

[jrichrds]

What transfer speeds do you get with the Coolmax enclosure?

 

[sathyan]

I'm also getting around the same speed. It takes 15 min to do a full backup of my data partition (10GB) to the external drive.
USB2 controller is NEC
USB2 enclosure is Bytecc
HDD in Enclosure is WD Caviar SE 80GB/7200rpm/8MB

I use it for backups and storing my A/V collection. The bandwidth is more than twice that required for full frame SDTV resolution AVI.