Never had this problem before with a motherboard not detecting a drive. Is it a BIOS issue that will be resolved once updated?
Check my spec page on user profile for my system info if this helps provide more info. It is running v4.1 and I can upgrade that to 4.3.
What happens is it will not detect the other HDD that windows is not installed on, but it didn't detect before any OS was installed on either drive, and this issue has been interchangeable between both HDDs. And each time Windows 7 setup detects both drives, not always - until I hot plug out and back in but it shows up then. Both HDDs show up when in windows but I run the risk of not being able to boot into windows having it connected. So as you can gather it is not RAID 0 as I normally have setup but AHCI for now. It is a new system and HDDs are healthy, pass all tests - and only a few months old.
I've not used AHCI mode before so howcome when I hotplug a HDD windows detects it but doesn't show up in computer, only under computer management? Only I could do with hotpluggin in a 2TB HDD I have that has backed up data on which I want to organised and move to another HDD so I can format it, I think it might be corrupted file system or something because when I hotplug it windows crashes whereas it never used to under my old system - this happens whether I use USB dock or SATA connection - hot plugging.
Advice much appreciated, thanks.