Mac Pro Quieter After Memory Upgrade?

It may seem strange, but after upgrading the stock 3GB memory to 16GB (OWC 4x4GB) it seems to run a little quieter now. It's a refurb 5,1 2.8 Quad that I got about 3 weeks ago and it was somewhat noisy. I thought maybe it had a fan bearing issue or something, but maybe not. Now with the memory upgrade and ML upgrade it seems to run much better and not as noisy. Anyone else ever hear of this or experience anything similar? Then I thought maybe removing the memory tray during the swap may have reseated it so its quieter? Well...I don't know. I'm just happy its a little quieter than it was for whatever reason.