In message , Steve Swift
writes
My preferred approach would be to buy four (or more) large SATA disks
and use them as a software RAID5 array.

I've always been fascinated by RAID arrays - especially their ability
to increase the size of your "disc" without ever going offline.
However, for domestic applications, the noise of four or more discs
could get quite distracting.
I used to run a mainframe disk subsystem that contained 60 PC disks.
You couldn't make yourself heard standing near it.

I am sitting here absorbing all of the posters generous advice with
amazement and gratitude. I won't comment for now except to say thank you
again and give copies of all the posts to the chap who is going to make
up my PC for me so he can "translate" it and use it to help me.
I will try to comment further after I have properly read and assimilated
all the advice herein.

Thank you all again.
--
Derrick Fawsitt