Hello everyone! I was doing an upgrade on my 2009 Mac Pro upgraded to 5,1 and noticed the North Bridge was wiggly, so I used some screws, sprints and nuts to re-secure it into place after getting rid of the regular Apple Northbridge holders. However, upon installing the new CPUs and booting - the GPU fans blast at full speed, I am greeted by a black screen and there is no chime. The CPUs I am using are Xeon x5670s. Now, I noticed that if I only have CPU A installed, the system boots and works well, it is only upon installation of CPU B that this occurs. I’ve used both CPUs in socket A to verify that they are working, so I’m stumped as to what is causing this problem. The pins seem to be in great condition from what I can tell. If anyone can shed some light on this it would be greatly appreciated!