Jos,

>>>>I'm looking at this USB flash memory card (apparently the thinnest in the world). On their spec sheet they state a read speed of 8MB/s over USB 2. How would that compare with an average PC drive these days?

>>Typical 7200 rpm drives can't sustain more than 65MB/sec (optimum), no matter the speed of the external interface. But that's still a lot faster than typical flash drives.
>
>Thanks Al. I had a suspicion the average HDD would be +/-10x the speed. I'm going to buy one today and see what its like. WIll let you all know.

>PS. If the 7200rpm is +/-65MB/sec, what would an average 5500rpm be +/-?

Al's numbers point you in the right direction. They are for the disks you have "experienced" in the last year. The new perpendicular recording enhances that speed by 25 to 35% while giving you larger capacity. But remember that the max speed is for the sectors in the outer rim only - it usually drops to some level between 45 and 66% of the max speed for the slowest speed in the inner sectors. The speeds for 3.5 5400 rpm are about 25% lower, but the "felt speed" is much more in line with 7200rpm disks, as the random access/seek times are similar. Those seek times are essentially eliminated in memory cards, making the "experience" faster when running applications and especially on booting, as then no data has been cached and the disks usually jump all over the OS dir.

Connecting via USB usually slows down external disks to 30 - 35MB/s, which means 2.5 disks are nearly as fast as external 3.5 disks, are easier to carry but have less capacity. So if your planned usage is more in the line of copy/filetransfer, you will wait clearly longer for the 1-3 CD's worth of data you fill into the "external": 4 minutes instead of 1. If you plan to run someting like vfp from a file on the "disk" on a RAM-starved laptop (no caching avalable) this will be much better, as the seek times favor the solid state. see

http://www.tomshardware.com/2006/09/20/conventional_hard_drive_obsoletism/

for similar comparison. But keep in mind that the base numbers between the solid disks are markedly different <g>.

regards

thomas