If you want the fan speed to be controlled by the PS2, as far as I know, it must be connected to the fan header pin location.
I have a PS2 v7 now. I also have parts from my original US launch model which was extremely high quality (in terms of build quality) compared to any other PS2 models I have encountered. I still have the fan from this model which is Japanese made and was very quiet/efficient from what I remember. It even had a mesh filter on it! They are both 7v but the amperage is slightly different. My question is, whether it would be safe to use this fan in the place of my v7 model.
The amperage shown on the fan isn't the amount of current the fan will receive, but the amount of current the fan will draw.
Remember to make sure that the fan blows in the correct direction before installing the fan, and that the leads should not be swapped around!
The fan might not fit mechanically, though.
I just swapped the nidec (vietnam made) one with a nbm (china made) one. The fan is .29a , the highest I have seen on a ps2 fan. The thing pushes nearly twice as much air as the stock nidec one but its even louder! lol. I am going to try swapping it with another model soon.
edit, also is the PS2 v7 prone to overheating? If It is I will leave this fan in there as it seems to be doing a good job cooling.
Is there a guide for this on PS2 slims? I'm looking for options to replace mine.
It would be just BETTER to mod your Ps2 with a bigger fan. Regardless of the version, just find out where 12v source points are. Then get a higher AMP fan either a 80mm or 92mm fan. It sounds like an OVERKILL, but it'll help both the CPU/GPU for cooling.