Hdd speed difference:- amazing difference

[slayek]

I have installed a Hitachi 7.2k rpm hdd in my Toshiba laptop and installed another external USB 2.0 based Toshiba 4.2k rpm hdd through a PCMCIA USB 2.0 extension and USB 2.0 4 port hub (yeah, I have just too many things to plugin to my laptop). The speed difference is however phenominal when I checked by Roadkil's disksped software. Any explanation why they differ so much? or is there a way to improve the external hdd's performance within USB 2.0 configuration? The internal hdd has write caching enabled while the external one is optimized for fast removal and I am using XPSP2 pro with 512MB RAM. Check out the screenshots going through this link, hdd-test.gif .

 

[UsandThem]

"The maxtor external hard drive realized the largest increase in transfer rate of the three peripherals we tested with USB 2.0 cards. The average time all five cards took to complete our file-copying task using the drive was 58 seconds, versus 12 minutes, 13 seconds with USB 1.1--12.6 times faster. The five-card average on our Photoshop test was 4 minutes, 24 seconds--8.5 times faster than the 37 minutes, 19 seconds that USB 1.1 took. Even so, our anecdotal analysis indicates that a 5400-rpm internal hard drive with a standard UDMA/100 bus still performs noticeably faster than our USB 2.0 drive.

Don't blame Maxtor's external drive for the slower performance--it's capable of sustained transfer rates of up to 46.7 MBps (about 374 mbps). That's slower than Hi-Speed USB's theoretical maximum, but much faster than the effective transfer rate of 11.2 MBps (90 mbps) we achieved in our file-copying task.

For answers, we turned to an executive at the USB Implementers Forum. First, according to Jason Ziller, chairman of the USB-IF and an Intel technology initiatives manager, at least 10 to 15 percent of the stated 60 MBps (480 mbps) of Hi-Speed USB goes to overhead--the communication protocol between the card and the peripheral. Overhead is a component of all connectivity standards."

With internal hard drives offering UDMA 100, 133, and 150 MBps (theoretical maximum as they don't hit that speed), internal hard drives will be much faster for the time being.

 

[flexy]

and the toshiba spins only at 4.2k which lead me to believe its really slow..in addition to the USB overhead etc...