Hello, first off thank you for reading this. I usually find out what I need through searching, but can't find anyone else having problems of this sort with this mini upgrade. I just bought a 4GB memory kit and a Seagate Momentus 7200.4 500GB for my spanking new mini. After installing everything the Mini crashes randomly in the form of a flickering garbled screen and speaker noise. So I was just wondering if anyone else has had (heat) issues with this drive, or had similar crashes and found the source of their problem. When the upgrade parts are installed the mini crashes after a while when running idle. It does not crash in single user mode, so Memtest OS X, and Apple Hardware tester shows no errors (no bad ram??). With the stock parts back in everything runs fine (no hardware errors), nor when booting from the Seagate mounted externally (no corrupt files). I'm thinking it could be one of three things. 1. Heat issue with drive 2. Faulty memory, despite 4 green runs of memtest os x. 3. Upgrade fail, and downgrade success. (loose connection) Cheers, Gabs.