I'm a beginner electronics enthusiast. I'm working on a variable power supply made from an ATX PSU. For the variable voltage output, I'm planning on using a step up module from the 12V 16A ATX in, boost it up to 30V then connect that to the step down converter for variable voltage. Is this ok? Should I be worried about efficiency? I'm planning on cooling both modules using a 12V fan.

 

Couldn't you use just a variable boost converter?
Welcome to AAC!

 

Couldn't you use just a variable boost converter?
Welcome to AAC!

I already bought the buck converter by mistake, and there's aren't any buck boost converter available in my country. The ones that are available are lower than 4A. I'm hoping to get around 8-10A. Are there any issues I should be aware of if I use both modules together?

Buck converter: https://www.electronics.com.bd/modules-shields/300w-20a-buck-converter
Boost converter: https://www.electronics.com.bd/modules-shields/dc-400w-boost-converter