It was recommended that I add RAM. I opened the box to see what I had and put it back in, and ever since then, the monitor will not display anything at all. The CPU sounds like it is booting, but the monitor display lights come on, and then it shuts down and will go no further. If I disconnect the cable from the back of the CPU, the monitor lights up, as soon as I replace the cabel, it goes black again.
The diagnostic lights are Amber Amber Green Green, and I heard three beeps when I booted initially after installing the RAM, but, not since.
Thanks for anything you can tell me. I am very new to these postings, so I hope I did it right.