
Originally Posted by
seasch
Hm. So your computer recognises both HDD, just not at the same time.
It could be, that the BIOS, if it is an older computer, prioritizes the IDE even when there is a SATA.
I would disconnect the IDE HDD, let the SATA HDD boot and check the BIOS settings. You should see the SATA as boot device.
Then reconnect the IDE, check BIOS and try to change the settings to how they were when the SATA was booting.
BIOS are often not very consumer-friendly. On this PC, for example, I need to select the HDD I want to boot from on an other page, than the start-up sequence. Updating the BIOS might also help.
Moving the SATA cable on the motherboard to the lower (usually SATA0) left might help too.