Thanks PP. But when I checked in regedit both the start values for pciide and storahci (which is now the MSahci after Goolking after I found I had noooo Msahci!) were both already set to 0 zero.
Tried again anyway, booting up and changing to AHCI in BIOS.
- With just the SSD connected I got the black screen of death again just after the BIOS version screen. It said Reboot amd select proper boot device or insert boot media and press any key.
- With the HDD it said 'inaccessible boot drive'.
I tried my Win 10 rescue disk above with the SSD and HDD and the options there (eg. autofix, re-install windows) but no luck.
Looked like this before I switched back to IDE:
So am now back to HDD on IDE again.
Should I just give up and go for a new Windows install on the SSD from scratch? I was hping to avoid this because I ahve Win 7 upgraded to Win 10 and all the SP1 downlooads for Win 7 will take ages.
Incidentally, my external backup disk got skewed during the fiddling above and said needed formatting. I have found a recovery program for the images and content which I'm running now. Have got most of it online already but fingers crossed.
Note to self - disconnect external drives when fiddling about. Just in case...!