After days of grueling work, I finally finished building my first computer but when I turned it on, it said it found no boot devices! I have a CD/DVD drive and SSD in the computer. Now, I know they work because the power cable is connected and they turn on. However, I am not sure if I connected them correctly. I have a SATA cable from the PSU connected to each and an ATA cable from the case connected to each. I'm not sure where to go from here .... Any suggestions would be appreciated. Thanks!