120gb ssd

Hello. I wanna buy 120GB drive only for OS (WIN10). I found one but im worried about temperatures due to graphics card heat when the M.2 will be underneath. Also i would be really thankful if you recommend me some SSD or M.2 for good price. Also if you wonder about the airflow i have 2x140mm...

I have Photoshop CC (CS7) and after spending some time on a project, moving layers, shapes, and panning(moving) around the project with the spacebar and mouse becomes so slow and laggy like it gets stuck or stutters. I have single channel (stupid me never got two sticks) 8gb of memory, and a GTX...