They don't need to be. That's the whole purpose of upgrading to a bigger drive. And yes cloning will copy everything over and you want have to reactivate anything. If you are going from a bigger drive to a smaller drive then you would have to shrink the original partition down to the size of the smaller drive if need be.
no,the drives dont have to be the same size,but the destination drive has to be big enough for all the data to be transferred of course.macrium is a good program.ive used it myself.if you have wd drives they have a free version of acronis true image.keep in mind that although this will transfer an os without the need to activate,it will only work on the computer with the source drive.
As has been said, the drives don't need to be the same size. In the past most people cloned from a smaller hdd to a larger hdd so that was no problem. However, nowadays many people are moving from a larger hdd to a smaller ssd. If the ssd isn't large enough to hold all the data currently on the hdd then it will require you to move data around to get the footprint small enough to be fit the ssd. That's why many use an ssd for boot/OS/programs and a larger hdd just for data.
Okay, I just put my 1TB HDD into my PC and formatted it as a new simple volume. All free space. This is now my E: drive.
My C: drive is using up 82GB with 156GB of free space. That's a SSD.
My D: drive is a 1TB SSHD. 157GB is being used for My Libraries (Documents, Music, Pictures, Videos). 774GB is still free.
What I want to do is this: I wanted to do a triple-boot. I read on the sticky that doing a dual-boot or even triple-boot is more advantageous than using a virtual drive. I'd also like to try setting it up this way anyway, because I've never tried it.
I wanted to have Windows 7, Windows 8, and some distro of Linux (probably Ubuntu) on one drive. However, I don't know how to go about doing it without running out of space on the SSD (C

. If I can fit everything that I only need on there, great, let me know. But then I would also need to figure out how to get it to point to My Libraries on the SSHD (D

. Then I'd use the HDD (E

for anything else that really doesn't need the faster read/write times. I'd really prefer not to save up for a bigger SSD drive though, if at all possible.
Also..would all the files in the Programs folders go into the C: drive or could they be accessed from a different drive altogether?
Sorry for writing so much.
