Hi, i have looked at several forums with similar issues, but I can seem to find out what the problem is and I hope maybe someone here can give me some ideas. I have a Mac Pro Mid 2010 A1289. The specs are... 3.33 GHz 6 Core Xeon W3680 1TB SSD 32gb RAM Nvidia Quadro 4000 graphics card It was running Yosemite 10.10.5 So, after the long New Year weekend I came in and turned it on but I got no display nor did I get the chime. The white power light stays on, the fans are humming, I removed the side panel and even the graphics card has a green light and its fan is running too. So I force a shut down and reboot. a small red light on the CPU Tray flashed and then nothing. I was back at the beginning. I tried to reset the PRAM, but with no chime or display, I don't think it was effective. I thought maybe the ram had gone bad, so I took out each one till i had none left and even still there was no change. I know the white light should flash is there is no ram, but it remain solid. I even tried booting it without the graphics card, just to see if I could hear a chime, but I could not. From what I've read this means I have a Bad CUP or a Bad PSU. I've tried putting in my old snow leopard disk to see if it would boot from that, but it wasn't very effective. Ive double checks all the connections and made sure everything was clean and snug. What do you think? Thanks in Advance!