The problem is that the emulator depends too much on the CPU and almost not on the video card. This is totally backwards as it should be in games. At least most of you should have noted that when you start a game (one of the more recent ones - after year 2000), you can see that the game itself doesn't load the CPU at max, but the video cart. I.e. if you buy an increadibly expensive video card and a little bit above the average CPU, you can play all the games at max, but the reverse config, doesn't prove that same results. Even the most demanding games nowadays don't load my CPU at the max, mostly 60 sometime 70%. The PCSX2 non stop keeps it at 100%. You can see what is the difference in for example 3d mark 03. You run some of the games with normal mode (presuring the video controller) and second using the CPU as PCSX2.
This is why no game can run properly and if the emulator doesn't start to use the resources and capabilities the video controller offers, we ain't gonna be able to play the games normally untill core 2 quad 5+ GHz doesn't come up.
All in all, respect to the developers to their devotion and hard work on the emulator!
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Don't change something when it works fine