Since most notebooks have USB 2 or newer ones USB 3.0 interfaces, even a slow HDD on SATA is faster than USB 3.0 so even if you did implement your RAID0 Asym system the USB interface would remove those gains.
-> Workaround? Max out the RAM in that notebook.
I replaced many notebook HD with SSD, so I collected many HD, which I plugged to my PC, and I want to take advantage of them.
I frequently use an HD for processing large files, so I would like to build a RAID0.
The problem is that those disks have different speeds, so if I make a RAID0, it will work at the speed of the slower one.
That would be solved if the RAID software were splitting each file in pieces whose size is proportional to the disk speed (even better if it also consider that the speed varies with the phicsical placement on the disk).
That way, small bits would be written on slow disks, and larger pieces on the faster ones.
But i do not know any software capable of doing it. Windows RAID0 is certainly not smart enough to take advantage of asymmetric HDs.
So the question is: there is any software RAID capable of creating asymmetric RAID?
Windows programs would be preferable, but also Linux solutions.