I understand how to connect pc fans to cell phone chargers but i just have a question about amps. If you have two pc fans that are 12v and use .16 amps and I only have either a 9v unkown amps charger or a 18v 3.5 amp charger which would be the better(safer) choice to use with both fans.
definitely just use any power supply 12v and under and you should be fine without blowing up the fan. 18v would fuck u over
pc fans are junk for ventilation, i would suggest looking into blowers/fans designed to be used as such.
between 9 and 18 use 9. 5v, 9v, 12v should all work okay, but as Doc mentioned they aren't going to be venting a lot of air, but they are good for a little air circulation inside a small chamber.