Dell XPS L1701X, it is now running Win 10 which Dell is not supporting in this machine, but I have had it installed now for 6 weeks and seems to be running fine. It has a 500 GB Western Digital original hard drive. I installed a second WD 500 GB hard drive in the second slot but it wasn't recognized by the BIOS or 'disk management' (it doesn't show up on either). I updated the BIOS to A10. I removed the second hard drive and then moved the original hard drive into the second slot and all is well. I put the new hard drive into the now vacant first slot and once again no recognition. Does anyone have any suggestions as to what may be wrong?
Note: I have posted this issue on the Dell community website twice in the past month but have received no help so I have pulled the Post.