I came across the Asus ITX-220 that uses 945GC and takes 4 GB or RAM. So apparently the chipset can take more than 2, but everybody else states it can't.
I obtained another Asus mainboard with 945GC chipset, and it does work with 4 GiB of RAM.
Furthermore, it goes faster than the 800 MHz FSB which is listed in
So are Intel publishing flawed specs, or Asus just clever at unlocking things?