Hey Phoenix , don't be a drongo or I'll hit you with a chozwozza
.
Anyways back to the subject.......
If your going to get a PSU try to get one thats a switchmode type , a switchmode PSU is smaller , lighter , more efficient , has better regulation and usually is cheaper.
With the current issue (get it , current issue) , if your 2200 needs 3.5 amps it will try to suck 3.5 amps out of your PSU so you will need a PSU supply that can supply 3.5 amps.
If your power supply can supply a bazzilion amps your 2200 will still try to suck 3.5 amps, the thing is try to get a PSU that can supply more than your 2200 needs ( but don't go overboard now ).
As an example here in Oz (stares at Phoenix
) a 12V PSU that can supply 5A costs about $35US
I hope this helps.
Oh and remember to check that the connector you use on the PSU is wired up OK ( the person who sold you the PSU should help you with this).
that's about it from me 8)
Mike 8)