No, the "minimum" specifications are lower (much), but that would be to just get the game running. For fullspeed, 3.2GHz (Core 2, I'm assuming) is what the team recommends as the starting point (do note that that although I say "starting point", it's still a recommendation that'll do okay, but they do advise more if possible). Since this is still a work in progress (hasn't reached version 1.0 yet), and many games aren't even able to run, while others need more than others, it's hard to give a recommendation. The recommendation is "throw the most speed at it as you can".
For PCSX2, "speed" means the most, well, speed. The best combination of IPC and frequency (which, currently, a Core 2 @4GHz and over is about at the top of) is the ideal solution, and it's better (essentially a requirement) that said CPU is also a dual ore CPU. No, PCSX2 does not benefit from quad cores, and if/when it does, the gains won't be big. It has to do with the way The Playstation 2 and PCSX2 is written that what they'd branch out may not net big gains. As it is, going from single core to dual core didn't net double the speed (though it was quite large a gain still).
So, as I said, having a quad core doesn't hurt, especially if/when support for them is added, but just having one at stock in the 2.xGHz range is no match for a dual core in the mid to upper 3.xGHz range, or worse, beyond. The dual core will smoke it.
Here's the recommended specifications I see going around.
CPU: Intel Core 2 @3.2GHz+ or similar/AMD equivalent
Ideal: Core 2 Penryn class @3.6GHz+/4.0GHz+ or similar/AMD equivalent
RAM: 1GB RAM (ungh, I think even 512MB may be okay, but any PC with that little RAM will likely not have the CPU for PCSX2 anyway)
GPU: nVidia GeForce 8600 GT/ATi equivalent or better (this is probably namely for DirectX 10 use, since the video plug-in goes faster in DirectX 10, as GPUs "lower" than it can do fine, so note that it's a recommendation)
Hm Maybe my Phenom II could be overclocked to over 4 Ghz but just now I don#t see any sense in that because my last try to get 2 of my cores enough work was yesterday while I tried 2 PCSX2 games at once.
Could it be that PCSX2 uses dualcore cpu's better when they are from Intel?
or are there secret options for dualcore cpu in an ini of it?
From what I see in your signature, I see you like to claim overclocking isn't needed, but you're spouting stuff that makes no sense.
First of all, two instances of PCSX2 would not only take up two cores (unless you had them running in single core mode, in which case they would not be running full speed unless it was a joke of a game requirements-wise). It matters not how many instances you have running if they're all less than full speed.
Secondly, as I said above, PCSX2 uses two threads, and two threads only. You gain
nothing from having two extra cores, so don't think it's helping in "the overall speed". It doesn't work to that mentality. You are, however, being hurt by having a lower speed. If you can get it to 4GHz, it's advised to do so and drop the charade. I'm sure it's a fast CPU. I know mine is still plenty fast at stock, but it's (your CPU) not a master of PCSX2, let alone two instances of it, without breaking a sweat or anything, like you're sounding.