Miray Forum

Information: Newest HD Clone Professional
Source 80GB Sata II Drive
Target 500 GB USB 2.0 External Drive
DISK to DISK option.

Problem: When we do the disk to disk copy it is only getting 20 MB/sec. USB 2 should go somewhere near 60 MB/sec. Also for note. we tried the 80 GB Sata II to a 250 GB Sata II and only got 54 MB/sec. COuld you let me know why this is happening and how we can improve the speed. It takes nearly 30 minutes to go from a sata II to a Sata II drive. It took 1 hour and 10 minutes to go to the usb drive.

Also, When copying back from the usb to a new sata drive it said it would take just over 3 hours?

Thanks

Your estimation of 60MB/s for USB is very very optimistic. USB has a gross speed of 480Mbit/s, which equals to 60MB/s, but in reality you won't find an USB drive faster than 30MB/s (if you're lucky, 20-25 are more the norm). Only USB 3.0 will bring amendments to this fact, but I suppose E-SATA will be the way to go for this purposes...

Sata Drives are capable of delivering from 50MB/s to more than 100MB/s, with smaller discs being slower (since less data travels under the pickup in the same amount of time). 60MB/s (or less) for a 80GB/s are quite common, though a bit on the lower performance side. Please observe that hard disks get slower the higher the sector number is, as on the inner side of the disc again less sectors are traveled in the same amount of time, so if a 80GB disc starts with 80MB/s, it's quite common for the disc to get as slow as 50MB/s at the end of the disc, making 70MB/s (or less) the average speed.

The 1:10 for SATA to USB should be ok, (70 minutes * 60seconds * 20MB/s = 84000MB), and if you copy the USB disc to a 250GB SATA disc it would just take again 250000MB/20MB/s = 3,5 hours.

Since You use HDCLone Professional, you can limit the amount of sectors to copy in one of two ways: a) use SmartCopy to copy only the data used on the disc, which will copy only 80GB at most, taking again 1:10 max for the way back.

Alternatively, since you came from a 80GB, note down the sector count of the 80GB (visible on the options dialog page), and later on use this value for the copy from USB to SATA to restrict the size again to 80GB instead of copying 250GB.