I have a self built custom made computer that is using a Ultra X3 1000 watt power supply. Over the years I have been reducing the power needs by adopting more energy efficient hardware. My computer is now using about 200 watts at any given time and can jump to a maximum of 360 or so when gaming or folding. So the PSU is overkill by 60% minimum.
I also have a 2560x1440 LG S-IPS LED monitor I built myself (63 watts max typical) using parts I sourced from around the globe and on eBay. The LG electronics that powers the monitor only needs a 24V 5A power brick for which I do not have yet. It is only $23 on ebay. However, I am wondering if I could use one of the empty +12V modular connectors on my PSU to supply the voltage/current to the monitor as well?
The PSU is a 85% efficient model with 70 amps on the +12V rail. I need to boost it to 24V, but I only need 5A according to the original power brick these come with.
Would a cheap DC-DC boost module work for this? Such as this boost converter.
The PSU I am using is connected to a very nice and conditioned power strip.
I am concerned that this boost converter says "Input current ：16A (MAX) (more than 10A please strengthen heatsink)". I thought current is only determined by the load draw required? Thus if the device I am powering only needs 5A at max, then why would I be concerned with the Input current of 70A? Isn't the input current just the maximum my PSU can supply, but draw is determined by the device using it?
My goal is to try and avoid using a cheap power supply, and saving a few bucks, and since my PSU is/was very expensive I consider it a much higher quality supply.
So can a boost converter do what I need to do safely? Or is this dangerous?