if i cant get a new hard drive, i'm going to back up internal. if i can backup, i want to have an external internal drive dock for backing up a 1.5tb drive, on a by weekly or monthly basis. haven't decided.
i don't have esata, so i would be using usb2.0
how long would it take to beck up a full 1.5tb hard drive through usb2.0 and would i be able to do other thing while its backing up?
i have dealt with drive cloning before, and that is a borderline dos thing in which for close to 6 hours i cant use the computer.
Realistic transfer rates for USB 2.0 are around 30MByte/sec. That translates to around 13-14 hours for 1.5TBytes.
Depending on the backup software you use, you can do other work, but that might (a) slow down the backup if you're heavily accessing files on the drive being backed up, and (b) prevent some files that are open from being backed up or possibly back them up in an inconsistent state if you're modifying them while they're being backed up.
My recommendation would be to run the backup overnight while you're not using the computer.