Hello all, I've been reading forums, blogs, and sites for a couple days about this issue but one thing never gets mentioned so I thought I would throw it out there and see if there's an answer. As the post title suggests, I have 17" Mid-2010 that came stock with 4GB. I bought 16GB (2x8) of RAM from OWC thinking that it would work because other mid-2010s seem to be able to upgrade to that. It doesn't and doesn't seem like that's possible because my proc is an i5. I get it, my bad. I blame no one but me for not reading the fine print. However, I can put the RAM in and Yosemite runs just fine...up to a point. In "About This Mac" it reports 16GB. If I have Activity Monitor up, I can watch the memory usage and it will crash just as it hits 4GB. The exact amount that this machine came with. That's just too much of a coincidence for me to buy. I flashed my NVRAM just in case a value for available RAM was stored there. That didn't help. Seeing as how it's possible to upgrade this model to 8GB, why doesn't it crash at the 8GB mark? Why always at 4GB (this is reproducible every time)? Thanks for any thoughts on this.