So I replaced my motherboard because my old one died and I'm having some trouble getting my 500gb hard drive to show up. My other 2tb works as well as my 840 evo and I can only get the 500gb to show up if I disable CSM compatibility in the bios which is supposed to help but alas I don't know so uh help. Motherboard is a asus m5a97 r2.0 on the latest bios and the hard drive is a samsung 502hj I'm not at home at the moment so I'll try anything when I get back also sorry for the wall of text on my phone.