You can run
AKReal with 16mb ram. Of course having a RTG like you makes things easier, although installing drivers for RTG won't be straight.
A3640?
25 or 50Mhz? It will work fast with 50Mhz, it would die with 25.
"This is your last chance. After this, there is no turning back. You take the blue pill—the story ends, you wake up in your bed and believe whatever you want to believe. You take the
AKReal pill—you stay in Wonderland, and I show you how deep the rabbit hole goes. Remember: all I'm offering is the truth. Nothing more."