Hi all, I have a Early 2011 2.2Ghz 15-inch MacBook Pro with a 750GB HDD in an MCE Optibay, and a 256GB Samsung 830 SSD in my main HDD slot. Very frequently and recently my Mac us locked up to the point where my cursor moves but Pages, or any app has a beachball. I can attempt to reload pages in Chrome, but I get stuck at "waiting for cache." The only solution was to force restart and then try to recover lost work, but it happens very frequently now. I thought at first it may be the HDD (where my home folder is, my startup disk is the SSD) because of Google Chrome's "waiting for cache," so I ran AHT to find that my 16 GB (2x8GB) Patriot 1333mhz RAM got the 4MEM/9 error (oddly, remover didn't see any issues). I am in the process of RMA'ing it back to Patriot, and for the time being am running off of a Corsair 2x4GB set. Initially the crashes and freezes stopped, but after a couple hours they returned. I ran AHT on this RAM to find that no errors were detected. Any thoughts on the underlying cause of this issue?