I tossed a 2gig ram stick into my Mini today, checked in bios on the way up and yup, it sees the 2 gigs of ram. Booted into Linux and found two very odd things in System Monitor... First of all, it shows 2 CPU's. WTF? Second, it only showed 886megs of ram. Strange.. So I did some more digging.. Finally ended up viewing /var/log/dmesg Right at the top of the log..
Warning only 896MB will be used.
Use a HIGHMEM enabled kernel.
896MB LOWMEM available.
Eee Gads! So the kernel will need to be recompiled to use the full amount of ram. 2gigs is kind of handy if you plan to run VirtualBox or VMWare..