Two 500gb HDD's, possibly failing or HDD setting???

Ok, I have two 500gb HDD's like the title says. Both are Seagate Barrucuda 7200.10's. Both were in a gaming PC I bought from a guy. He booted and let me look at it, and even test Bioshock infinite and skyrim on it. Now these HDD's had windows 8 on them before, but I wanted windows 7, so I went ahead with the installation not thinking about the secure boot. Get on their, and says it won't let me doing anything because of secure boot. So I get the idea to go to the other HDD, and put windows 7 on it. That one seemed ok with letting me format and install on it. So I figured, ok, just got to boot from this HDD instead, and format the other one from within, or find a work around. Well windows 7 let me create a user, everything going fine, even formatted over the other HDD and basically took it over with windows 7 (Not sure if this is a fail on windows 8 part letting me do it, or if the HDD was acting up???). Anywho, install some games, going great, playing the games. Now I was just doing normal day to day tasks, and windows 7 starts acting up, almost like it was slowly wasting away, then couldn't boot into windows 7 anymore, saying no MBR could be found. So I re-installed windows 7, installed games again, same thing happened again... Try to re-install windows 7 a third time, and it says it can't on both HDD's because of secure boot. So my first thought, was the motherboard was the culprit. Tried both HDD's on different PC with windows 7, and it said no to formatting because of secure boot. I then tried on a linux based pc, to see if I could format over it with any of their formats, said no to that to. Then tried DBAN, and couldn't boot it because secure boot wouldn't let it. OK, so now I use a different HDD from a different computer, a Samsung 120gb, in the gaming computer, to see if it would work ok and everything. Install windows 7, install video games, play video games. Everything was fine! No issues whatsoever. I order a 120gb intel SSD, switch it out, install windows 7 etc etc... Worked fine with the SSD as well, no issues. So anywho, what does everyone think??? Are they failing or is this an HDD setting holding onto the windows 8 secure boot possibly??? Let me know what you all think, any possible solutions... Would be nice to save a whole 1tb of memory from being trash .

P.S. When I would check the motherboard for the gaming PC, secure boot option to turn off and on, was not present at all, for any storage device installed on it, including both 500gb HDD's. Lastly, I noticed the number 2 500gb HDD, would sometimes not be detected, and this was on all computers I tried it on, with all motherboards. Number 1 500gb HDD, was detected all times.

P.S.S I made sure everything was spinning and moving on the inside, so nothing is dead dead...