I noticed there were a few threads about this where some people weren't able to resolve this issue wherein the computer turns on but doesn't boot up as well as the monitor not getting any signal AFTER trying to install or uninstall RAM. I came to this forum after having the same issue wherein I installed my RAM modules and seemingly nothing I tried worked. I'm not actually asking a question with this message, merely hoping to help those with similar problems...
When a tech person asks you, "Are you sure the memory is properly seating in its housing, or securely in place?" or something to that effect, what people don't realize, and myself included, is that it may LOOK like it's properly seated, but in fact it's not!
How to tell?
1. Don't just slide in your memory sticks. Do you see the clamps that hold it in on the top and bottom within the CPU? Keep both of those open.
2. When you have the memory stick lined up within it the memory housings, push down on the top side first. DO NOT PUSH DOWN THE CLAMPS WITH YOUR HANDS. PUSH IN THE MEMORY STICK UNTIL THE CLAMP SECURES BY ITSELF! And do the same thing with the other end. This is very important to do this on both ends of the memory housing, because if you don't, the memory in fact is not properly or securely placed and the computer will turn on and not boot up.
Everyone who's had this exact same problem, please retry this because I don't want you all to get rid of a properly running Mobo due to the memory not being securely in place.