Will the old Apple 29 watt bricks made for the iPhone X fast charge the iPhone 12 pro max ?

[ekneeiphone]

Good morning folks,
It has been widely reported that in order to fast charge the new iPhone 12 series ( approximately 50 percent in a half hour) you need to use the 20 watt apple brick or similar product from 3rd parties.
I have some old 29 watt apple bricks which I purchased around the time of the X or x plus which were touted as fast chargers for the iPhone.
Does anybody know if those 29 watt bricks will fast charge the iPhone 12 pro max ( approximately 50 percent in 30 minutes) or do I need to buy the 20 watt for this to occur.

Thank you.

 

[nr2d]

I read somewhere that unless you use the MAGSAFE charger the charge rate in limited to either 7.5 or 10 watts. This includes hardwired plug in and using a a 3rd party wireless charger.

 

[Wotchered]

If I remember correctly, to fast charge you need a usb c outlet wall charger (18w +) and a usb c to lightning cable to maximise charge rate. I am still playing with this in a desultory sort of way, and the one lesson I have learnt is, the cable must be the best you can find !