So I got an old Dell Optiplex 7010 and I was planning on putting a graphics card in it and making it a nice running pc. I decided that I would have to upgrade the power supply so I could use the GPU, and so I used a OCZ Fatal1ty 550W power supply from an old build we had laying around. It is semi modular so it came with cords at one point but we lost the cords and so we decided to order some from EBay, it said they were for the 1000W model but we didn’t think that mattered so we ordered them. They just came in today so when I went to plug in my graphics card the front power button blinks yellow and the computer doesn’t turn on. I’m not sure what to do, any help in appreciated.