Hdd Not showing anywhere after installing!! nitro 5

Nabhan25

Hi, 
I have a nitro 5 and since it has a extra hdd slot, I thought I would intall a hdd. I installed a used hdd but it was in good condition and worked perfectly. With the help of the online official guide and some youtube vidoes i managed to install and after putting on the cover and before putting back the screws i tested if it was working. To my surprise it actually worked. The drive was showing up everywhere and it worked perfectly. So I shutdown the laptop and put the screws back on but this time it took a while to boot up. after it boot up when i checked that deive was not showing anywhere. I checked bios and everything. So I took apart the laptop once again to see if I connected it wrong ( it wasen't). After re checking and re-connecting everything i once again booted it up without screwing. It worked. i Even re started the laptop to see if it was alright and it was. So put the screws back and booted it. This time to took longer just like the last time. and again the drive was not showing. 
Anyone know why this his happerning???
Im 100% sure i didn't brreak anything. HDD also works. 

Thread was edited to add model name to the title

Commodore_1995#

I also had a similar problem on my an515-54. For some reason, I believe that the lowe case keeps pressing this cable, causing some kind of bad contact: