Ssd not recognized slowing down pc

Focus99

Reputable
Aug 1, 2014
12
0
4,510
So I am running a home build that was previous to purchasing this sad running flawlessly.
Amd fx 8350
Gigabyte 990 fxa
8gb ram
650w corsair psu
80gb hdd (old boot drive)
550hb D drive
Now I uninstalled the 80gb drive installed the ssd (pny 256gb) ran a fresh install of windows 8.1 on the ssd. Windows took over 4hrs to install and once it did my CPU was running extremely slow doing basic tasks. My bios settings are on achi I have since deleted windows off the ssd unplugged the D drive made sure bios was on achi and reinstalled windows to no avail. Also sometimes bios won't recognize the sad at all. When I rebooted after the first windows install the sad wasn't found at all and I'm intermittently having this same problem. I'm lost on this one need some help please