How to connect a second switchable power supply?

Question

Iron

Welcome all!
There is a small PC based on an i3 processor and a micro ITX motherboard, which acts as both a desktop and a router for me (on 24/7). There is an economical power supply unit with a power of 150 watts from the Khetai brothers in mind. At the peak of the load, I never consumed more than 60-70 watts. On board 1 SSD, 2 HDD, i3 and integrated vidyakha.
I want to be able to gamble on it from time to time. How can I best implement this?
options:
1 (ideal): Buy a PSU and a vidyakha, and somehow make the power supply of the vidyakha from the 2nd PSU. With a switch that if the card is not used, just turn off the 2nd more powerful power supply. Is this even possible?
* and again the question is from here, what will happen if the 2nd PSU is turned off, and the video card is turned off, but it will stick out in the pci-e slot on the mother. Will the system work from an integrated low-power video card?
2: just when you need to play, stick a video card into the mother and plug the power wire from a low-power power supply unit to a more powerful one. The inconvenience of course in peretykanie. I don’t want to spin a powerful power supply 24 hours a day so that the PC works like a router, this is not economically beneficial for me.
Can you tell me the best way to do it?

Answer 1

1. Graphics cards receive up to 75W through the PCI-E slot. I have big doubts that the second block can be turned off.
It's just not trivial to do two asset-asset blocks. There is a noticeable problem - the video card is exclusively + 12V power. Not every power supply will normally react to the consumption of tens of amperes at + 12V and zero - at + 3.3V and + 5V
2. "from the Khetai brothers". One good more powerful PSU can have higher efficiency at low load. Economically ... Let's say that the PSU has an efficiency of around 0.7 due to the low power consumption (and even this is a low figure among state employees). Let's say your 150W has an efficiency in the region of 0.85 - this is a very good indicator for 1/3 of the rated power. We recalculate from consumption to 50 watts.
Chinese will eat 59W, 42kW*h per month
budget more powerful - 71W, 51kW*h per month
decent PSU efficiency 0.8 62W, 45kW*h
How much do you cost 3kW*h? Are you sure that your Chinese PSU has an efficiency of 0.85? And not 0.7? Or even not 0.6?
Oops, distracted, already painted everything before me.

Answer 2

All modern power supplies have a PFC module. They convert as much power as the computer consumes. There is no point in your idea - just buy one powerful PSU.