1.9GHZ VS 1.2GHZ

[xsacha]

Well it depends on the game. Let's just say that there is a hypothetical game (eg. PES 2013) that uses both the CPU and GPU heavily.
Let's just say the game requires at least 1.3GHz to generate 60 frames and it requires at least a Medium GPU to render 40 frames and a Strong GPU to render the 60 frames.
Noting that there is a linear association with CPU performance and VPS and that there is a more exponential performance with GPU performance and FPS (weak GPUs can barely run anything).

1.9GHz + Strong GPU = 60 VPS (and 60 FPS) perfectly playable (smooth)
1.9GHz + Medium GPU = 60 VPS (and 40 FPS) playable, some frame skips. (may be regarded as smooth)
1.9GHz + Weak GPU = 60 VPS (and 15 FPS) not playable, heavy frame skipping

1.2GHz + Strong GPU = 55 VPS (and 55 FPS) perfectly playable (smooth)
1.2GHz + Medium GPU = 55 VPS (and 40 FPS) playable, some frame skips. (may be regarded as smooth)
1.2GHz + Weak GPU = 55 VPS (and 15 FPS) not playable, heavy frame skipping

0.8GHz + Strong GPU = 37 VPS (and 37 FPS) playable, no frame skip. (smooth but not real-time)
0.8GHz + Medium GPU = 37 VPS (and 37 FPS) playable, no frame skip. (smooth but not real-time)
0.8GHz + Weak GPU = 37 VPS (and 15 FPS) not playable, heavy frame skipping

Note: GHz listed assuming same architecture (Cortex-A9 for eg.)
Note: if the game is able to use the game timer hack (available for Symbian only at this stage) like Wipeout, it will have always 60 VPS regardless of CPU performance but FPS is still limited by frames generated by CPU. That is, game speed is always real-time and no frame skipping.