wmk
re Incremental Backups;
Represents only the changed sectors of the volume since the last full or incremental backup was taken. Each incremental backup image is dependent on all prior incremental backup images and the full backup image related to the backup job. By selecting to mount or restore an incremental backup image, you are incorporating the contents of the full backup image and any prior incremental backup images to create a complete representation of the volume at the point-in-time of the incremental image you are using.
Because incremental backup images only involve the changed sectors, these backup images can be written very fast compared to full or differential backup images.
With Shadow Protect for example,a background incremental may take only seconds
Differential;
Represent the changes relative to another backup image file. Differential backup images can be taken against a full backup image.
A differential backup requires approximately the same amount of time to generate as a full backup image, but will require less space since it only consists of the changed sectors relative to the image file the differential was generated against.
A lot of non commercial users just settle for full backups,as it doesn't normally take long ,takes up little actual space , isn't dependent on all the links in the chain being OK or on amalgamating all the separate images into one to conserve space
re speeds;
An external drive using an usb 2.0 interface will achieve 20-30 Mps(megabytes per second) vs 75-85 Mps for eSATA
re problems;
Acronis users have reported problems when using USB-see their forums.
My problem with eSata was for some unknown reason ,it seemed to be incompatible with Creative software and card,if plugged in continuously,causing hardware interrupts.
I now plug in only when required and copy the backup image there,rather than backup direct.
My main backup archives are the different separate internal partitions
You may have no problems whatsoever with either and eSata should not have any problems normally at all-so dont be put off!
However,I would recommend using eSata.
re AHCI;
AHCI is the acronym for the Advanced Host Controller Interface. It enables advanced SATA features like Native Command Queuing (NCQ) and hot-plugging. Unless it is specifically enabled, the SATA controller will run in IDE emulation mode.
With Hot Plugging eSATA can be activated anytime,but in IDE mode only at computer boot up.
If its not a selectable mode on your computer,it indicates that the required Intel software isnt present.
Difficult to install and not really required.