I think the bottleneck is due to the 4700 having an external videochip as opposed to the X30, which lets the CPU handle graphics.
The 4700 has the ATI 3220 videochip, the same one in the Toshiba e800. It is not known to be a fast chip unless an application is written to support it, if such support helps at all. Most games and emulators so far do not rely on any video acceleration. Check out the following link: to see how the 400MHz e800 with the ATI 3220 gets beatened by the 400MHz Dell X3i (index 1352 vs 1911).
If you still think the slowness is due to the VGA screen of the e800, then look at the slow speed of the 400MHz XDA II with the ATI 3200 chip: index 1382.
I hope the intel 2700G chip doesn't have the same bottleneck as other video chips.